Radio frequency refers to a group of electromagnetic radio waves that is used for commercial broadcasting and transmitting wireless telecommunications signals.
You can think of electromagnetic waves as a filing cabinet. There is one drawer labeled “Radio Frequency.” Inside it are dividers describing how the frequency will be used. One is tagged “FM Radio and TV”. Another is assigned to “Electronic communication devices” (which includes WiFi).
Specific radio frequencies are assigned to different applications so they do not overlap. Otherwise, the applications could step on each others’ toes, and telecommunications would be a mess.
Other interesting terms…