"the whole nine yards"?

What does it mean when someone uses "the whole nine yards" in a sentence?

It kinda means they put in 100% they went the whole way, got the job done with a little extra.

But I am not sure were it comes from.

I was going to answer but rotis got it right... it means going all the way, giving your all..

        Simply a Rose to brighten your day,
        And maybe lessen the cares in your way;
        And also, too, to help you to know,
        That in knowing you, many others grow!

 
Take your pick, whatever suits your fancy:

http://www.straightd...

The same as "the whole enchilada!" Ever heard of "lock, stock, and barrel?" That would be a "turn key operation", meaning: Getting the keys to the door, everything in the store and on the shelves, and the building in a purchase agreement.
Some others might be a van with power washing equipment for car dealer lots, a truck with machines and candy as a vendor would use, etc.