We are not so familiar with that. Available also from internet through telnet. Many people use dos when they use internet. Terminal to unix machine, unix programs. Less and less internet provider offer this kind of connection to the internet.
Many people are afraid to use windows.
Some also linux Many have started to use windows, some also internet, Eudora, Netscape, Internet Explorer. Not yet courses. Guidelines how to do good web pages for visually impaired. Projects on internet. Published booklets how to use word and win 95 without mouse and when you just see one line or part of the screen.