This document discusses different types of instructional software. It defines instructional software as programs designed to deliver or assist with student instruction on a topic. There are two main types discussed: drill-and-practice software and tutorial software. Drill-and-practice software provides exercises for students to reinforce learning through feedback, while tutorial software provides a full instructional sequence on a topic similarly to a teacher's classroom lessons. The document provides criteria for selecting good software for each type and discusses benefits and limitations of using instructional software in teaching.