1. The document discusses various audio-visual aids used in educational technology like charts, flannel boards, magnetic boards, bulletin boards, flash cards, cutouts, and models.
2. It describes each aid in terms of what it is, how it is used, and the advantages it provides in teaching.
3. Educational technology also includes hardware tools for teaching like radio broadcasts, audio and video players, tape recorders, computers, and projectors which can be used to disseminate educational content to students.