Computer-assisted instruction (CAI) refers to using computers to provide drill-and-practice, tutorials, or simulations to students, while computer-managed instruction (CMI) uses computers to track student progress and provide individualized learning objectives and resources. CAI involves direct interaction between students and educational software, and can take forms like drill-and-practice, tutorials, games, simulations, discovery, and problem-solving. CMI allows instructors to manage instruction for individual students and choose objectives and activities based on their needs. Both approaches provide benefits like self-paced learning and immediate feedback but also have limitations like over-reliance on multimedia or lack of infrastructure.