Print :
Textbooks, Study Guides, Workbooks - Are still very common in online learning courses.
Audio :
Streaming audio - Used to deliver the instructors comments over any network.
Audio tapes - Could be mailed to students.
Video :
Streaming video - Can deliver video over any network.
Videotape - Could be produced and mailed to students.
Cable TV - Course segments can be produced and aired in various locations nationwide.
Data:
Web Pages - A very common form of delivering content.
CBT Content - Often delivered via CD-ROM, but also deliverable via a network.
Computer files - Can be emailed or downloaded from a server (word processor, spreadsheet, presentation, database, etc.).
Online Tests - Computer scripts can be written to deliver a variety of test formats.
Interactive Tools - The following tools can also be used to deliver content to learners.
Asynchronous :
Email - Used for questions and discussion.
Listservs - Basically email to everyone in the class or section at once.
Web Forums - Also called discussion forums or bulletin boards. They are probably the most common form of interaction in online courses.
Newsgroups - Public forums that use the Usenet system.
BBS - A computer bulletin board that you dial, and use like a web forum + email + file transfer.
Synchronous :
Chat Rooms - Can be either moderated by an instructor of un-moderated for class use.
Shared Whiteboards - Allow class members to write on the same digital whiteboard.
Application Sharing - The same program and file can be shared for demonstration or collaboration.
Teleconferencing - Could be used to deliver instructor audio, or for collaboration.
Videoconferencing - Either from expensive, high quality, dedicated systems, or from less reliable desktop versions.
MOOs & MUDs - Virtual worlds where users take on avatars and interact in various ways.