This document explains the concept of a system and its basic components such as input, process, and output, highlighting the distinction between manual and computer-based information systems. It outlines the System Development Life Cycle (SDLC) phases, which include requirements identification, solution design, coding, testing, deployment, and maintenance, along with various deployment strategies and models. Additionally, it details methods of gathering information during the initial requirements phase, such as observation, interviews, and prototyping.