drivers are sort of 'helper programs' that tell the Operating System (windows XP, Vista, Ubuntu, you name it) what to do when you want to use some bit of hardware; sound, video, printing, etc.
Essentially there should be one for every device that performs a distinct function. When you want to play a video, a driver tells your sound card what the file you're using (wav, mp4, whatever) is, then puts the data in a form the sound card can understand. Instant sound.
What you'll need to do is figure out what devices you have in your system. If you have a Windows Operating system, try going to Control Panel, System, and then Device Manager. If you click on the + signs, you can find out what each device is called (there's other ways to do this, but this is the simplest one I could think of at the time...past my bedtime...
Then you'll need to find out which companies' sites might have the drives. Or, there's Linux forums all over the net, they might have a way to tell you where to go to get them.
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