When speaking on a walkie-talkie why does one answer "Roger"?

[wickedangel]

You know, when they say "Roger that".

 

[summer]

Because their name is Roger.

 

[glent]

originally used for radio transmissions to let the other end know that you were done talking to which the answering end would acknowledge with Wilco, roger then went on to mean OK, I understand, just shortening the words needed to send a message here are some sites to look up