The wonderful service the phone brings us, of course, is not free. Long-distance calls vary depending on the distance between the caller and receiver and for how long they talk. Since Bell's first telephone, various kinds of telephony have been developed. For example, transoceanic cables have allowed people to talk on the phone overseas since 1956. Now, optical fiber telephony have made transoceanic cables obsolete.
Fiber optics allows phone calls to be coded into light pulses and sent through glass fibers.
Microwave relay is another way to transfer large amounts of phone calls, however the extent of microwave relay is limited because between the sending and receiving stations must be in a clear line of sight. Last, satellite telephony has been a very effective way of sending and receiving telephone calls since 1969. A series of satellites receive messages and then retransmitts them to another part of the world. A recent development in technology has allowed people to view the person they are talking to. A limited number of these phones are available and they are expensive.