A lighting desk is what is used the majority of the time to control lights for a play, concert, or other type of show. (The alternative being to use a computer which has the capability of providing a DMX-512 output to control the lights)

There are loads of different makes of lighting desk - one of the more popular makes being Strand (everything from the tiny 6-channel control box (it's too small to call a desk) to something huge and complex that I've never seen, and don't know what it's called). The majority of desks will have memories, which enable you to store a set number of cues in the desk. These can be traversed through with the simple press of the go button during a show. The sequential memory functions of a desk are more often used in plays, rather than concerts.

For concerts, the lighting desk is often laid out slightly differently. Rather than just have a sequence of cues, there will be a number of groups of presets. Each one, for example, will have a number of presets for it, which the lighting operator can change between (or have more than one on at once) using flash buttons. This can be a lot more useful during a concert when the lights need to be timed to the music, and where it couldn't be an exact sequence of cues.

If you're after any other theatre tech information, then do take a look at 'Everything you ever wanted to know about theatre tech, but were afraid to ask'