Students entering beginning computer courses have a wide range of experiences with and prior learning in the use of computers. Additionally, adult learners who have returned to school at the community college level may be apprehensive and anxious about computer use. A hypertext computer-assisted instruction (CAI) program was developed in order to teach the disk operating system (DOS) to beginning classes with different backgrounds. The CAI program was demonstrated in class, and the students used the program in a computer lab. The results showed that more students passed a DOS proficiency test after eight weeks using the CAI method than students using the traditional method. Student attitudes also improved. It may be concluded, based on these results, that the hypertext CAI software program should be considered for beginning classes. Appendices include the hypertext CAI documentation and the program handout. (26 references) (DB)