Don't touch that dial, give it up for...

I have two interrogants,

what does it means when they say on tv :
"don't touch that dial", where does the expression come from?

and also what does it means when they say something like :
"Give it up for (Chris Rock, Britney Spears, or any other artist)

"don't touch that dial" - "dial" in this case refers to the remote control, so when they say "don't touch that dial" they mean don't change the channel.

"Give it up for (Chris Rock, Britney Spears, or any other artist)" means "Clap your hands and applaude".

The expression does mean don't turn the channel, but dail doesn't refer to the remote control. It refers to the channel dail that used to be on televisions. There were two dails, one to turn the tv on/off and another to turn the channel.

Example: http://www.acsu.buffalo.edu/~lmkinney/lauren/television.jpg

<<There were two dails, one to turn the tv on/off and another to turn the channel.>>

I'm dating myself here, but actually, there was one dial to turn the VHF channel, and another to turn the UHF channel.

Thanks Guest, I didn't quite remember and my sister said it was on/off.