This document discusses educational technology, defining it as the process of applying tools and media for educational purposes. It outlines the evolution of educational technology from audiovisual communications and instructional systems to computers and computer-based systems. Key aspects covered include defining computer hardware and software, describing components like CPUs and memory, and examining the development of educational technology systems from mainframes to today's networked personal computers and applications. Current uses of educational technology systems focus on instructional software, interactive media, distance learning, productivity tools, and tools to help students with tasks.