This document provides an overview of the internal components of a computer and their functions. It discusses the central processing unit (CPU) as the brain of the computer, random access memory (RAM) for short-term use by the CPU, the hard drive for long-term storage, the video/graphics card for displaying images, audio/sound card for sound, USB card for connecting peripherals, and the power supply unit. It notes that laptop components are smaller versions of the same parts wired together on a motherboard. The document also previews topics to be covered in future sessions, including saving files, using Windows, and working with sound and video.