A digital voice keyer is kind of like an automated tape recorder, with control circuits available for for radio.  With VKE, you can record a message, such as "CQ CQ Contest from N7QJP" to be used during a contest.  When you play back the message, it keys your transmitter at the beginning of the message and unkeys it at the end.

VKE allows you to repeat the message automatically, with a pause between transmissions so you can monitor for another station returning your call.  When band conditions are down a bit, or the QSO rate is low, having a voice keyer do the CQing for you can be a life saver....ok, a voice saver.

VKE also has special timing routines for 15 second meteor scatter QSOs.  VKE uses your computer's sound card to record and playback any messages you need for contesting, meteor scatter contacts, or casual CQs and station IDs.