get is like a tape recorder. Entering a get command while in command mode is like loading a blank cassette tape into the recorder. While in talk mode, you press a special hot key (the copy key) to pause or restart the tape. get will record everything that you receive while get is turned on, just like a tape recorder. You can turn the recorder on or off by pressing the copy key again.
send is like a tape player. Entering a send command is like loading a prerecorded tape into the player. While in talk mode, you press the put key to start the tape. send will "play back" everything in the file while it is turned on, just like a tape player. You can turn the playback on or off by pressing the put key again.
get and send transfer only text files and don't provide any error checking. They are very unsophisticated, but they provide a simple way to move text from one system to another. get is also useful for recording a log of your activity on the remote computer.