IXC's and PBX's. T-1, ATM, and ISDN. If you've ever struggled to understand telecommunications, you know that the industry has some of the most incomprehensible jargon of any technical field. Worse yet, telecommunications is an area that's fast growing and fast changing, so each month produces more baffling acronyms. If you need help, consider Newton's Telecom Dictionary, by Harry Newton (Flatiron Publishing, New York City, 800-542-7279, 1994, $24.95). The latest edition of this comprehensive tome contains definitions for thousands of terms in telecommunications as well as such related fields as computer networking. Telecommunications expert Newton aims to write definitions in nontechnical language, and his 1,000-page-plus book is both exhaustive and surprisingly down-to-earth. However, Newton doesn't always succeed in keeping his definitions jargon free, so you may end up consulting several definitions before a concept really makes sense. Still, if you need to keep up with telecommunications technology, this dictionary will help.

* * *