What is a printer driver?

WHAT IS A PRINTER DRIVE??? okay this is my problem, im trying to copy my pixma MP 495 printr files off my XP windows computer and put them on my flash drive so i can install my printer on my new Windows 7 computer. but i looked on google and it seems like i can download the software (since i can't find the cd) off of google to install my printer on the windows 7 computer. is this possible? and am i going in the right direction?What is a printer driver?
yes go to computer manf website and search printer driver after your model number

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