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A telephone call is a connection over a telephone network between the calling party and the called party.
A telephone call may carry ordinary voice transmission using a telephone, data transmission when the calling party and called party are using modems, or facsimile transmission when they are using fax machines. The call may use land line, cell phone, satellite phone or any combination thereof. Where a telephone call has more than one called party it is referred to as a conference call. When two or more users of the network are sharing the same physical line, it is called a party line or Rural phone line.
Calls are usually placed through a network (such as the Public Switched Telephone Network) provided by a commercial telephone company. If the caller's wireline phone is directly connected to the calling party, when the caller takes their telephone off-hook, the calling party's phone will ring. This is called a hot line or ringdown. Otherwise, the calling party is usually given a tone to indicate they should begin dialing the desired number. In some (now very rare) cases, the calling party cannot dial calls directly, and is connected to an operator who places the call for them.
Most telephone calls in the world are set up using ISUP messages or one of its variants between telephone exchanges to establish the end to end connection.
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