Abbreviation of Federal Communications Commission. Among its duties in regulating public airwaves in the United States, the FCC is responsible for rating personal computers and other equipment as either Class A or Class B. The ratings indicate how much radiation a personal computer emits. Almost all personal computers satisfy Class A requirements, which means they are suitable for office use. Class B machines, which are suitable for use anywhere (including the home), must pass more stringent tests. Class B indicates that the machine's radio frequency (RF) emissions are so low that they do not interfere with other devices such as radios and TVs.