RAEN and RAYNET both stand for "Radio Amateurs' Emergency Network". They are sister organisations providing the same services, not rivals like the BBC and ITV. Individual members belong more or less randomly to one or the other, depending on which their local group decided to join. Operations often draw members from nearby groups, regardless of whether they are RAYNET or RAEN.
The term RAYNET is often used generically to indicate both groups. The User Services (those who use RAYNET) simply call the telephone number they have been given, regardless of which group it is.
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