It intermittenly types letters and numbers that I don't tap. It also will type words out of the sequence in which I typed them. Bizarre. Can anyone tell me what could be causing this?

Is this a wireless keyboard? More information would be helpful.

Keyboards are pretty basic, usually. If it's just a regular laptop keyboard, built into the laptop, then Id say it probably one of three things:
1. Crumbs/Dust/Junk under the keys. Get a can of compressed air, hold the laptop upside down, and try blowing it out, to see if it works better
2. Faulty keyboard. If it's still under warranty, see if they'll replace it. Otherwise, you'll have to get a new one (or a used one)
3. Bad connection. You could try to take the keyboard out, clean the contacts, and then put it back in, making sure you connect the little ribbon cable securely (It's usually not too hard to take a laptop keyboard out... generally, pry the plastic piece around or above it off, then take out a few screws. You might be able to find instructions for it on the manufacturers website, or by searching google)

Hi, I tried a system restore and that actually corrected the problem. Thanks for taking the time to answer my question.