Editing Signals intelligence (section)

===Voice interception===
A basic COMINT technique is to listen for voice communications, usually over radio but possibly "leaking" from telephones or from wiretaps. If the voice communications are encrypted, traffic analysis may still give information.

In the Second World War, for security the United States used Native American volunteer communicators known as [[code talker]]s, who used languages such as [[Navajo language|Navajo]], [[Comanche]] and [[Choctaw]], which would be understood by few people, even in the U.S. Even within these uncommon languages, the code talkers used specialized codes, so a "butterfly" might be a specific Japanese aircraft. British forces made limited use of [[Welsh language|Welsh]] speakers for the same reason.

While modern electronic encryption does away with the need for armies to use obscure languages, it is likely that some groups might use rare dialects that few outside their ethnic group would understand.