This document provides an introduction to subnetting and IP addressing. It begins with an overview of Todd Lammle and his background in networking certification. It then covers basic topics in IP addressing like binary numbering, IP address classes, and subnet masks. The bulk of the document focuses on explaining how to determine subnets, broadcast addresses, and host ranges for a given IP address and subnet mask through a process of asking six questions. It provides numerous examples of subnetting different IP addresses with different subnet masks.