![1. How are a computer's internal components physically linked? Illustrate the concept by describing a complete machine cycle.2. On most computers, all internal components are designed around a common wordsize. Why? Explain how a computer wordsize affects its processing speed, memory, capacity, precision, and instruction set size.3. What is meant by computer's architecture?4. Discuss the ff: terms: Motherboard, slot, bus, network, signal, local area network, wide area network, network server, workstation, host5. Briefly describe the different network topologiesYou may use images, links, documents or videos to present your discussion. Be more creative in the way you present your answers.Deadline for posting your assignments: JULY 13, 2010<br /> 1.Internal components are the devices that are inside the main computer tower. These devices include the Central Processing Unit (CPU), Motherboard and the modem.<br />Computer Hardware is the physical part of a computer, as distinguished from thecomputer softwarethat executes or runs on the hardware. The hardware of a computer isinfrequently changed, while software and data are modified frequently. The term \"
soft\"
refers to readily created, modified, or erased. Theseare unlike the physical components within the computer which are \"
hard\"
. <br />Inside Computer<br />Motherboard<br />The motherboard is the \"
body\"
or mainframe of the computer, through which all other componentsinterface. It is thecentral circuit board making up a complex electronic system. A motherboard provides the electrical connections by which the other components of the systemcommunicate. The mother board includes many components such as: centralprocessing unit (CPU), random access memory (RAM), firmware, and internal and external buses.<br />Motherboard<br />Central Processing Unit<br />The Central Processing Unit (CPU; sometimes just called processor) is amachine that can executecomputer programs It is sometimes referred to as the \"
brain\"
of the computer.<br />CPU Diagram<br />There are four steps that nearly all CPUs use in their operation:fetch, decode, execute, and writeback. The firststep, fetch, involves retrieving an instruction from program memory. In thedecode step, the instruction is broken up into parts that have significance toother portions of theCpu. During the execute step various portions of the CPU such as the arithmeticlogic unit (ALU) and thefloating point unit (FPU) are connected so they can perform the desired operation. The final step, writeback, simply \"
writes back\"
the results of the execute step to some form of memory.<br />Random Access Memory<br />Random access memory (RAM) is fast-access memory that is cleared when the computer is power-down. RAM attaches directly to the motherboard, and is used to store programs that are currently running. RAM is a set of integrated circuits that allow the stored data to be accessed in any order (why it is called random). There are many different types of RAM. Distinctions between these different types include: writable vs. read-only, static vs. dynamic, volatile vs. non-volatile, etc.<br />RAM<br />Firmware<br />Firmware is loaded from the Read only memory (ROM) run from the BasicInput-Output System (BIOS). It is a computer program that is embedded in a hardware device, for example a microcontroller. As it name suggests, firmware is somewhere between hardware and software. Like software, it is a computer program which is executed by a microprocessor or a microcontroller. But it is also tightly linked to a piece of hardware, and has little meaning outside of it. Most devices attached to modern systems are special-purpose computers intheir own right, running their own software. Some of these devices store that software (\"
firmware\"
) in a ROM within the device itself<br />Power Supply<br />The power supply as its name might suggest is the device that supplies power to all the components in the computer. Its case holds a transformer, voltage control, and (usually) a cooling fan. The power supply converts about 100-120 volts of AC power to low-voltage DC power for the internal components to use. The most common computer power supplies are built to conform with the form factor. This enables different power supplies to be interchangable with different components inside the computer. ATX power supplies also are designed to turn on and off using a signal from the motherboard, and provide support for modern functions such as standby mode.<br />Removable Media Devices<br />If your putting something in your computer and taking it out is most likely a form of removable media. There are many different removable media devices. The most popular are probably CD and DVD drives which almost every computer these days has at least one of. There are some new disc drives such as Blu-ray which can hold a much larger amount of information then normal CDs or DVDs. One type of removable media which is becoming less popular is floppy disk.<br />CD<br />CDs are the most common type of removable media. They are inexpensive but also have short life-span. There are a few different kinds of CDs. CD-ROM which stands for Compact Disc read-only memory are popularly used to distribute computer software although any type of data can be stored on them. CD-R is another variation which can only be written to once but can be read many times. CD-RW (rewritable) can be written to more than once as well as read more than once. Some other types of CDs which are not as popular include Super Audio CD (SACD), Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD.<br />CD-ROM DriveThere are two types of devices in a computer that use CDs: CD-ROM drive anda CD writer. The CD-ROM drive used for reading a CD. The CD writer drive canread and write a CD. CD writers are much more popular are new computers than aCD-ROM drive. Both kinds of CD drives are called optical disc drives becausethe use a laser light or electromagnetic waves toread or write data to or froma CD.<br />2. Word Size the number of bits in a computer word. In computing, word is a term for the natural unit of data used by a particular computer design. A word is simply a fixed sized group of bits that are handled together by the system. The number of bits in a word (the word size or word length) is an important characteristic of computer architecture.<br />The size of a word is reflected in many aspects of a computer's structure and operation; the majority of the registers in the computer are usually word sized and the amount of data transferred between the processing part computer and the memory system, in a single operation, is most often a word. The largest possible address size, used to designate a location in memory, is typically a hardware word (in other words, the full sized natural word of the processor, as opposed to any other definition used on the platform).<br />Modern computers usually have a word size of 16, 32 or 64 bits but many other sizes have been used, including 8, 9, 12, 18, 24, 36, 39, 40, 48 and 60 bits. The slab is an example of a system with an earlier word size. Several of the earliest computers used the decimal base rather than binary, typically having a word size of 10 or 12 decimal digits and some early computers had no fixed word length at all.<br />The size of a word is sometimes defined to be a particular value for compatibility with earlier computers. The most common microprocessors used in personal computers (for instance, the Intel Pentiums and AMD Athlons) are an example of this; their IA-32 architecture is an extension of the original Intel 8086 design which had a word size of 16 bits. The IA-32 processors still support 8086 (x86) programs, so the meaning of word in the IA-32 context was kept the same, and is still said to be 16 bits despite the fact that they at times (especially when the default operand size is 32 bits) operate largely like a machine with a 32 bit word size, similarly in the newer x86-64 architecture a word is still 16 bits, although 64-bit (quadruple word) operands may be more common.<br />3.COMPUTER ARCHITECTURE<br />In computer science and computer engineering, computer architecture or digital computer organization is the conceptual design and fundamental operational structure of a computer system. It is a blueprint and functional description of requirements and design implementations for the various parts of a computer, focusing largely on the way by which the central processing unit (CPU) performs internally and accesses addresses in memory.<br />It may also be defined as the science and art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals.<br />Computer architecture comprises at least three main subcategories: HYPERLINK \"
http://en.wikipedia.org/wiki/Computer_architecture\"
\l \"
cite_note-0\"
[1]<br />Instruction set architecture, or ISA, is the abstract image of a computing system that is seen by a machine language (or assembly language) programmer, including the instruction set, word size, memory address modes, processor registers, and address and data formats.<br />Microarchitecture, also known as Computer organization is a lower level, more concrete and detailed, description of the system that involves how the constituent parts of the system are interconnected and how they interoperate in order to implement the ISA.[2] The size of a computer's cache for instance, is an organizational issue that generally has nothing to do with the ISA.<br />System Design which includes all of the other hardware components within a computing system such as:<br />System interconnects such as computer buses and switches<br />Memory controllers and hierarchies<br />CPU off-load mechanisms such as direct memory access (DMA)<br />Issues like multiprocessing.<br />Once both ISA and microarchitecture have been specified, the actual device needs to be designed into hardware. This design process is called implementation. Implementation is usually not considered architectural definition, but rather hardware design engineering.<br />Implementation can be further broken down into three (not fully distinct) pieces:<br />Logic Implementation — design of blocks defined in the microarchitecture at (primarily) the register-transfer and gate levels.<br />Circuit Implementation — transistor-level design of basic elements (gates, multiplexers, latches etc) as well as of some larger blocks (ALUs, caches etc) that may be implemented at this level, or even (partly) at the physical level, for performance reasons.<br />Physical Implementation — physical circuits are drawn out, the different circuit components are placed in a chip floorplan or on a board and the wires connecting them are routed.<br />For CPUs, the entire implementation process is often called CPU design.<br />4. A motherboard is the central printed circuit board (PCB) in many modern computers and holds many of the crucial components of the system, while providing connectors for other peripherals. The motherboard is sometimes alternatively known as the main board, system board, or, on Apple computers, the logic board.[1] It is also sometimes casually shortened to mobo.<br />*A local area network (LAN) is a computer network covering a small physical area, like a home, office, or small groups of buildings, such as a school, or an airport. The defining characteristics of LANs, in contrast to wide area networks (WANs), include their usually higher data-transfer rates, smaller geographic area, and lack of a need for leased telecommunication lines.<br />*A computer network, often simply referred to as a network, is a collection of computers and devices connected by communications channels that facilitates communications among users and allows users to share resources with other users. Networks may be classified according to a wide variety of characteristics. This article provides a general overview of types and categories and also presents the basic components of a network.<br />*Slot, a space for a container on a ship, usually expressed as a 20' or 40' slot (ie 20 or 40 feeT.<br />*The most common type of bus is the single-decker bus, with larger loads carried by double-decker buses and articulated buses, and smaller loads carried by midibuses and minibuses. A luxury, long distance bus is called a coach. A bus is usually powered by a combustion engine, although early buses were horse drawn and there were experiments with steam propulsion. Trolleybuses use overhead power lines. In parallel with the car industry bus manufacturing is increasingly globalised, with the same design appearing around the world.<br />*A workstation is a high-end microcomputer designed for technical or scientific applications. Intended primarily to be used by one person at a time, they are commonly connected to a local area network and run multi-user operating systems. The term workstation has also been used to refer to a mainframe computer terminal or a PC connected to a network. Historically, workstations had offered higher performance than personal computers, especially with respect to CPU and graphics, memory capacity and multitasking capability. They are optimized for the visualization and manipulation of different types of complex data such as 3D mechanical design, engineering simulation (e.g. computational fluid dynamics), animation and rendering of images, and mathematical plots. Consoles consist of a high resolution display, a keyboard and a mouse at a minimum, but also offer multiple displays, graphics tablets, 3D mice (devices for manipulating and navigating 3D objects and scenes), etc. Workstations are the first segment of the computer market to present advanced accessories and collaboration tools.<br />*A wide area network (WAN) is a computer network that covers a broad area (any network whose communications links cross metropolitan, regional, or national boundaries[. This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively.<br />WAN design options<br />WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization's LAN to the Internet. WANs are often built using leased lines. At each end of the leased line, a router connects to the LAN on one side and a hub within the WAN on the other. Leased lines can be very expensive. Instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods. Network protocols including TCP/IP deliver transport and addressing functions. Protocols including Packet over SONET/SDH, MPLS, ATM and Frame relay are often used by service providers to deliver the links that are used in WANs. X.25 was an important early WAN protocol, and is often considered to be the \"
grandfather\"
of Frame Relay as many of the underlying protocols and functions of X.25 are still in use today (with upgrades) by Frame RelaX<br />*A network server is a computer designed to process requests and deliver data to other (client) computers over a local network or the Internet. Examples include Web servers, proxy servers, and FTP servers. Not only should you be familiar with using servers on the Internet, an increasing number of people hvae learned to set up network servers for business and personal uses.<br />*In the fields of communications, signal processing, and in electrical engineering more generally, a signal is any time-varying or spatial-varying quantity. In the physical world, any quantity measurable through time or over space can be taken as a signal. Within a complex society, any set of human information or machine data can also be taken as a signal. Such information or machine data (for example, the dots on a screen, the ink making up text on a paper page, or the words now flowing into the reader's mind) must all be part of systems existing in the physical world – either living or non-living. Despite the complexity of such systems, their outputs and inputs can often be represented as simple quantities measurable through time or across space. In the latter half of the 20th century, electrical engineering itself separated into several disciplines, specializing in the design and analysis of physical signals and systems, on the one hand, and in the functional behavior and conceptual structure of the complex human and machine systems, on the other. These engineering disciplines have led the way in the design, study, and implementation of systems that take advantage of signals as simple measurable quantities in order to facilitate the transmission, storage, and manipulation of information.<br />5. Network topology is defined as the interconnection of the various elements (links, nodes, etc.) of a computer network.[1][2] Network Topologies can be physical or logical. Physical Topology means the physical design of a network including the devices, location and cable installation. Logical topology refers to the fact that how data actually transfers in a network as opposed to its physical design.<br />Topology can be considered as a virtual shape or structure of a network. This shape actually does not correspond to the actual physical design of the devices on the computer network. The computers on the home network can be arranged in a circle shape but it does not necessarily mean that it presents a ring topology.<br />Any particular network topology is determined only by the graphical mapping of the configuration of physical and/or logical connections between nodes. The study of network topology uses graph theory. Distances between nodes, physical interconnections, transmission rates, and/or signal types may differ in two networks and yet their topologies may be identical.<br />A Local Area Network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN has one or more links to one or more nodes in the network and the mapping of these links and nodes in a graph results in a geometrical shape that may be used to describe the physical topology of the network. Likewise, the mapping of the data flow between the nodes in the network determines the logical topology of the network. The physical and logical topologies may or may not be identical in any particular network.<br />In computing, word is a term for the natural unit of data used by a particular computer design. A word is simply a fixed sized group of bits that are handled together by the system. The number of bits in a word (the word size or word length) is an important characteristic of computer architecture.<br />The size of a word is reflected in many aspects of a computer's structure and operation; the majority of the registers in the computer are usually word sized and the amount of data transferred between the processing part computer and the memory system, in a single operation, is most often a word. The largest possible address size, used to designate a location in memory, is typically a hardware word (in other words, the full sized natural word of the processor, as opposed to any other definition used on the platform).<br />Modern computers usually have a word size of 16, 32 or 64 bits but many other sizes have been used, including 8, 9, 12, 18, 24, 36, 39, 40, 48 and 60 bits. The slab is an example of a system with an earlier word size. Several of the earliest computers used the decimal base rather than binary, typically having a word size of 10 or 12 decimal digits and some early computers had no fixed word length at all.<br />The size of a word is sometimes defined to be a particular value for compatibility with earlier computers. The most common microprocessors used in personal computers (for instance, the Intel Pentiums and AMD Athlons) are an example of this; their IA-32 architecture is an extension of the original Intel 8086 design which had a word size of 16 bits. The IA-32 processors still support 8086 (x86) programs, so the meaning of word in the IA-32 context was kept the same, and is still said to be 16 bits despite the fact that they at times (especially when the default operand size is 32 bits) operate largely like a machine with a 32 bit word size, similarly in the newer x86-64 architecture a word is still 16 bits, although 64-bit (quadruple word) operands may be more common.<br />](https://image.slidesharecdn.com/ghelos-100712044131-phpapp02/85/Ghel-os-1-320.jpg?cb=1278910211)
Ghel os
- 1. 1. How are a computer's internal components physically linked? Illustrate the concept by describing a complete machine cycle.2. On most computers, all internal components are designed around a common wordsize. Why? Explain how a computer wordsize affects its processing speed, memory, capacity, precision, and instruction set size.3. What is meant by computer's architecture?4. Discuss the ff: terms: Motherboard, slot, bus, network, signal, local area network, wide area network, network server, workstation, host5. Briefly describe the different network topologiesYou may use images, links, documents or videos to present your discussion. Be more creative in the way you present your answers.Deadline for posting your assignments: JULY 13, 2010<br /> 1.Internal components are the devices that are inside the main computer tower. These devices include the Central Processing Unit (CPU), Motherboard and the modem.<br />Computer Hardware is the physical part of a computer, as distinguished from thecomputer softwarethat executes or runs on the hardware. The hardware of a computer isinfrequently changed, while software and data are modified frequently. The term \" soft\" refers to readily created, modified, or erased. Theseare unlike the physical components within the computer which are \" hard\" . <br />Inside Computer<br />Motherboard<br />The motherboard is the \" body\" or mainframe of the computer, through which all other componentsinterface. It is thecentral circuit board making up a complex electronic system. A motherboard provides the electrical connections by which the other components of the systemcommunicate. The mother board includes many components such as: centralprocessing unit (CPU), random access memory (RAM), firmware, and internal and external buses.<br />Motherboard<br />Central Processing Unit<br />The Central Processing Unit (CPU; sometimes just called processor) is amachine that can executecomputer programs It is sometimes referred to as the \" brain\" of the computer.<br />CPU Diagram<br />There are four steps that nearly all CPUs use in their operation:fetch, decode, execute, and writeback. The firststep, fetch, involves retrieving an instruction from program memory. In thedecode step, the instruction is broken up into parts that have significance toother portions of theCpu. During the execute step various portions of the CPU such as the arithmeticlogic unit (ALU) and thefloating point unit (FPU) are connected so they can perform the desired operation. The final step, writeback, simply \" writes back\" the results of the execute step to some form of memory.<br />Random Access Memory<br />Random access memory (RAM) is fast-access memory that is cleared when the computer is power-down. RAM attaches directly to the motherboard, and is used to store programs that are currently running. RAM is a set of integrated circuits that allow the stored data to be accessed in any order (why it is called random). There are many different types of RAM. Distinctions between these different types include: writable vs. read-only, static vs. dynamic, volatile vs. non-volatile, etc.<br />RAM<br />Firmware<br />Firmware is loaded from the Read only memory (ROM) run from the BasicInput-Output System (BIOS). It is a computer program that is embedded in a hardware device, for example a microcontroller. As it name suggests, firmware is somewhere between hardware and software. Like software, it is a computer program which is executed by a microprocessor or a microcontroller. But it is also tightly linked to a piece of hardware, and has little meaning outside of it. Most devices attached to modern systems are special-purpose computers intheir own right, running their own software. Some of these devices store that software (\" firmware\" ) in a ROM within the device itself<br />Power Supply<br />The power supply as its name might suggest is the device that supplies power to all the components in the computer. Its case holds a transformer, voltage control, and (usually) a cooling fan. The power supply converts about 100-120 volts of AC power to low-voltage DC power for the internal components to use. The most common computer power supplies are built to conform with the form factor. This enables different power supplies to be interchangable with different components inside the computer. ATX power supplies also are designed to turn on and off using a signal from the motherboard, and provide support for modern functions such as standby mode.<br />Removable Media Devices<br />If your putting something in your computer and taking it out is most likely a form of removable media. There are many different removable media devices. The most popular are probably CD and DVD drives which almost every computer these days has at least one of. There are some new disc drives such as Blu-ray which can hold a much larger amount of information then normal CDs or DVDs. One type of removable media which is becoming less popular is floppy disk.<br />CD<br />CDs are the most common type of removable media. They are inexpensive but also have short life-span. There are a few different kinds of CDs. CD-ROM which stands for Compact Disc read-only memory are popularly used to distribute computer software although any type of data can be stored on them. CD-R is another variation which can only be written to once but can be read many times. CD-RW (rewritable) can be written to more than once as well as read more than once. Some other types of CDs which are not as popular include Super Audio CD (SACD), Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD.<br />CD-ROM DriveThere are two types of devices in a computer that use CDs: CD-ROM drive anda CD writer. The CD-ROM drive used for reading a CD. The CD writer drive canread and write a CD. CD writers are much more popular are new computers than aCD-ROM drive. Both kinds of CD drives are called optical disc drives becausethe use a laser light or electromagnetic waves toread or write data to or froma CD.<br />2. Word Size the number of bits in a computer word. In computing, word is a term for the natural unit of data used by a particular computer design. A word is simply a fixed sized group of bits that are handled together by the system. The number of bits in a word (the word size or word length) is an important characteristic of computer architecture.<br />The size of a word is reflected in many aspects of a computer's structure and operation; the majority of the registers in the computer are usually word sized and the amount of data transferred between the processing part computer and the memory system, in a single operation, is most often a word. The largest possible address size, used to designate a location in memory, is typically a hardware word (in other words, the full sized natural word of the processor, as opposed to any other definition used on the platform).<br />Modern computers usually have a word size of 16, 32 or 64 bits but many other sizes have been used, including 8, 9, 12, 18, 24, 36, 39, 40, 48 and 60 bits. The slab is an example of a system with an earlier word size. Several of the earliest computers used the decimal base rather than binary, typically having a word size of 10 or 12 decimal digits and some early computers had no fixed word length at all.<br />The size of a word is sometimes defined to be a particular value for compatibility with earlier computers. The most common microprocessors used in personal computers (for instance, the Intel Pentiums and AMD Athlons) are an example of this; their IA-32 architecture is an extension of the original Intel 8086 design which had a word size of 16 bits. The IA-32 processors still support 8086 (x86) programs, so the meaning of word in the IA-32 context was kept the same, and is still said to be 16 bits despite the fact that they at times (especially when the default operand size is 32 bits) operate largely like a machine with a 32 bit word size, similarly in the newer x86-64 architecture a word is still 16 bits, although 64-bit (quadruple word) operands may be more common.<br />3.COMPUTER ARCHITECTURE<br />In computer science and computer engineering, computer architecture or digital computer organization is the conceptual design and fundamental operational structure of a computer system. It is a blueprint and functional description of requirements and design implementations for the various parts of a computer, focusing largely on the way by which the central processing unit (CPU) performs internally and accesses addresses in memory.<br />It may also be defined as the science and art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals.<br />Computer architecture comprises at least three main subcategories: HYPERLINK \" http://en.wikipedia.org/wiki/Computer_architecture\" \l \" cite_note-0\" [1]<br />Instruction set architecture, or ISA, is the abstract image of a computing system that is seen by a machine language (or assembly language) programmer, including the instruction set, word size, memory address modes, processor registers, and address and data formats.<br />Microarchitecture, also known as Computer organization is a lower level, more concrete and detailed, description of the system that involves how the constituent parts of the system are interconnected and how they interoperate in order to implement the ISA.[2] The size of a computer's cache for instance, is an organizational issue that generally has nothing to do with the ISA.<br />System Design which includes all of the other hardware components within a computing system such as:<br />System interconnects such as computer buses and switches<br />Memory controllers and hierarchies<br />CPU off-load mechanisms such as direct memory access (DMA)<br />Issues like multiprocessing.<br />Once both ISA and microarchitecture have been specified, the actual device needs to be designed into hardware. This design process is called implementation. Implementation is usually not considered architectural definition, but rather hardware design engineering.<br />Implementation can be further broken down into three (not fully distinct) pieces:<br />Logic Implementation — design of blocks defined in the microarchitecture at (primarily) the register-transfer and gate levels.<br />Circuit Implementation — transistor-level design of basic elements (gates, multiplexers, latches etc) as well as of some larger blocks (ALUs, caches etc) that may be implemented at this level, or even (partly) at the physical level, for performance reasons.<br />Physical Implementation — physical circuits are drawn out, the different circuit components are placed in a chip floorplan or on a board and the wires connecting them are routed.<br />For CPUs, the entire implementation process is often called CPU design.<br />4. A motherboard is the central printed circuit board (PCB) in many modern computers and holds many of the crucial components of the system, while providing connectors for other peripherals. The motherboard is sometimes alternatively known as the main board, system board, or, on Apple computers, the logic board.[1] It is also sometimes casually shortened to mobo.<br />*A local area network (LAN) is a computer network covering a small physical area, like a home, office, or small groups of buildings, such as a school, or an airport. The defining characteristics of LANs, in contrast to wide area networks (WANs), include their usually higher data-transfer rates, smaller geographic area, and lack of a need for leased telecommunication lines.<br />*A computer network, often simply referred to as a network, is a collection of computers and devices connected by communications channels that facilitates communications among users and allows users to share resources with other users. Networks may be classified according to a wide variety of characteristics. This article provides a general overview of types and categories and also presents the basic components of a network.<br />*Slot, a space for a container on a ship, usually expressed as a 20' or 40' slot (ie 20 or 40 feeT.<br />*The most common type of bus is the single-decker bus, with larger loads carried by double-decker buses and articulated buses, and smaller loads carried by midibuses and minibuses. A luxury, long distance bus is called a coach. A bus is usually powered by a combustion engine, although early buses were horse drawn and there were experiments with steam propulsion. Trolleybuses use overhead power lines. In parallel with the car industry bus manufacturing is increasingly globalised, with the same design appearing around the world.<br />*A workstation is a high-end microcomputer designed for technical or scientific applications. Intended primarily to be used by one person at a time, they are commonly connected to a local area network and run multi-user operating systems. The term workstation has also been used to refer to a mainframe computer terminal or a PC connected to a network. Historically, workstations had offered higher performance than personal computers, especially with respect to CPU and graphics, memory capacity and multitasking capability. They are optimized for the visualization and manipulation of different types of complex data such as 3D mechanical design, engineering simulation (e.g. computational fluid dynamics), animation and rendering of images, and mathematical plots. Consoles consist of a high resolution display, a keyboard and a mouse at a minimum, but also offer multiple displays, graphics tablets, 3D mice (devices for manipulating and navigating 3D objects and scenes), etc. Workstations are the first segment of the computer market to present advanced accessories and collaboration tools.<br />*A wide area network (WAN) is a computer network that covers a broad area (any network whose communications links cross metropolitan, regional, or national boundaries[. This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively.<br />WAN design options<br />WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization's LAN to the Internet. WANs are often built using leased lines. At each end of the leased line, a router connects to the LAN on one side and a hub within the WAN on the other. Leased lines can be very expensive. Instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods. Network protocols including TCP/IP deliver transport and addressing functions. Protocols including Packet over SONET/SDH, MPLS, ATM and Frame relay are often used by service providers to deliver the links that are used in WANs. X.25 was an important early WAN protocol, and is often considered to be the \" grandfather\" of Frame Relay as many of the underlying protocols and functions of X.25 are still in use today (with upgrades) by Frame RelaX<br />*A network server is a computer designed to process requests and deliver data to other (client) computers over a local network or the Internet. Examples include Web servers, proxy servers, and FTP servers. Not only should you be familiar with using servers on the Internet, an increasing number of people hvae learned to set up network servers for business and personal uses.<br />*In the fields of communications, signal processing, and in electrical engineering more generally, a signal is any time-varying or spatial-varying quantity. In the physical world, any quantity measurable through time or over space can be taken as a signal. Within a complex society, any set of human information or machine data can also be taken as a signal. Such information or machine data (for example, the dots on a screen, the ink making up text on a paper page, or the words now flowing into the reader's mind) must all be part of systems existing in the physical world – either living or non-living. Despite the complexity of such systems, their outputs and inputs can often be represented as simple quantities measurable through time or across space. In the latter half of the 20th century, electrical engineering itself separated into several disciplines, specializing in the design and analysis of physical signals and systems, on the one hand, and in the functional behavior and conceptual structure of the complex human and machine systems, on the other. These engineering disciplines have led the way in the design, study, and implementation of systems that take advantage of signals as simple measurable quantities in order to facilitate the transmission, storage, and manipulation of information.<br />5. Network topology is defined as the interconnection of the various elements (links, nodes, etc.) of a computer network.[1][2] Network Topologies can be physical or logical. Physical Topology means the physical design of a network including the devices, location and cable installation. Logical topology refers to the fact that how data actually transfers in a network as opposed to its physical design.<br />Topology can be considered as a virtual shape or structure of a network. This shape actually does not correspond to the actual physical design of the devices on the computer network. The computers on the home network can be arranged in a circle shape but it does not necessarily mean that it presents a ring topology.<br />Any particular network topology is determined only by the graphical mapping of the configuration of physical and/or logical connections between nodes. The study of network topology uses graph theory. Distances between nodes, physical interconnections, transmission rates, and/or signal types may differ in two networks and yet their topologies may be identical.<br />A Local Area Network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN has one or more links to one or more nodes in the network and the mapping of these links and nodes in a graph results in a geometrical shape that may be used to describe the physical topology of the network. Likewise, the mapping of the data flow between the nodes in the network determines the logical topology of the network. The physical and logical topologies may or may not be identical in any particular network.<br />In computing, word is a term for the natural unit of data used by a particular computer design. A word is simply a fixed sized group of bits that are handled together by the system. The number of bits in a word (the word size or word length) is an important characteristic of computer architecture.<br />The size of a word is reflected in many aspects of a computer's structure and operation; the majority of the registers in the computer are usually word sized and the amount of data transferred between the processing part computer and the memory system, in a single operation, is most often a word. The largest possible address size, used to designate a location in memory, is typically a hardware word (in other words, the full sized natural word of the processor, as opposed to any other definition used on the platform).<br />Modern computers usually have a word size of 16, 32 or 64 bits but many other sizes have been used, including 8, 9, 12, 18, 24, 36, 39, 40, 48 and 60 bits. The slab is an example of a system with an earlier word size. Several of the earliest computers used the decimal base rather than binary, typically having a word size of 10 or 12 decimal digits and some early computers had no fixed word length at all.<br />The size of a word is sometimes defined to be a particular value for compatibility with earlier computers. The most common microprocessors used in personal computers (for instance, the Intel Pentiums and AMD Athlons) are an example of this; their IA-32 architecture is an extension of the original Intel 8086 design which had a word size of 16 bits. The IA-32 processors still support 8086 (x86) programs, so the meaning of word in the IA-32 context was kept the same, and is still said to be 16 bits despite the fact that they at times (especially when the default operand size is 32 bits) operate largely like a machine with a 32 bit word size, similarly in the newer x86-64 architecture a word is still 16 bits, although 64-bit (quadruple word) operands may be more common.<br />