Phreaking

Phreaking is a slang term coined to describe the activity of a culture of people who study, experiment with, or explore, telecommunication systems, such as equipment and systems connected to public telephone networks. The term phreak is a sensational spelling of the word freak with the ph- from phone, and may also refer to the use of various audio frequencies to manipulate a phone system. Phreak, phreaker, or phone phreak are names used for and by individuals who participate in phreaking.

The term first referred to groups who had reverse engineered the system of tones used to route long-distance calls. By re-creating these tones, phreaks could switch calls from the phone handset, allowing free calls to be made around the world. To ease the creation of these tones, electronic tone generators known as blue boxes became a staple of the phreaker community, including future Apple Inc. cofounders Steve Jobs and Steve Wozniak.

The blue box era came to an end with the ever increasing use of computerized phone systems, which sent dialing information on a separate, inaccessible channel. By the 1980s, much of the system in the US and Western Europe had been converted. Phreaking has since become closely linked with computer hacking. This is sometimes called the H/P culture (with H standing for hacking and P standing for phreaking).

Phone phreaking got its start in the late 1950s in the United States. Its golden age was the late 1960s and early 1970s. Phone phreaks spent a lot of time dialing around the telephone network to understand how the phone system worked, engaging in activities such as listening to the pattern of tones to figure out how calls were routed, reading obscure telephone company technical journals, learning how to impersonate operators and other telephone company personnel, digging through telephone company trash bins to find "secret" documents, sneaking into telephone company buildings at night and wiring up their own telephones, building electronic devices called blue boxes, black boxes, and red boxes to help them explore the network and make free phone calls, hanging out on early conference call circuits and "loop arounds" to communicate with one another and writing their own newsletters to spread information.

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