Computers--and the community of people that surrounds them--do an excellent job of generating jargon. They"ve created a world of RJ-11 jacks, Lempel Ziv compression, TACACS protocols, and data forks. Microsoft Computer Dictionary, Fourth Edition, explains all these terms and thousands more. It"s a sort of miniencyclopedia of computing topics. The dictionary focuses on providing beginning and intermediate computer users with a solid grounding in terms, technologies, and concepts related to productivity software, databases, and networks. Communications technologies--such as those related to mobile phones--get attention too. This latest edition of the dictionary includes a selection of terms related to the Year 2000 bug, though these terms are inexplicably isolated in a special appendix. The Microsoft Computer Dictionary generally treats non-Microsoft technologies evenhandedly--the entries related to Sun Microsystems" Java language might even be construed as boosterish. However, a Microsoft slant sometimes appears, as in the coverage of palm-size PCs. There"s no mention of 3Com"s topselling Palm computers or its operating systems, though Windows CE is mentioned. Cross-referencing, particularly of acronyms, is excellent. The companion CD-ROM allows you to quickly search for dictionary terms and also includes The Microsoft Manual of Style for Technical Publications. --David Wall