where did the term TIPS come from and what does it stand for?

There are like 10 definitions for "Tip". Are you referring to "Tip" as in the act of "Tipping"?

as in tipping in restaurants, etc....

The popular explanation of the origin of tip, meaning a gratuity, is that it is an acronym meaning "to ensure promptness." This is incorrect.

Tip means to pass on, to hand to, especially to pass on a small sum of money. It dates to at least 1610. The verb meaning to give a gratuity dates to about a century later, and the noun dates to at least 1755. Anf as far as I know, there are no pre-20th century acronymic word origins.

I had always heard it was an acronym for "to insure prompt service"...

that's what I had heard too "to insure prompt service"....I've heard that they actually used change so that it made noise as they placed it into a cup/bucket on the table - they would place the coins in it throughout the night as the service was received.....

could be wrong though....as so many things have different origins.

Lydia,
The coins making sounds in the cups reminds me of the Seinfeld episode when George attempts to retrieve his tip from a plastic jar at a pizza place because nobody saw him placing it in there and he felt it didn't count -- I like the noise thing -- calls attention to our generosity!!