burette-taken from labtitan.co.uk
pipette-taken from globalscientific.com
With a pipette you use a suction bulb to gather a specific amount of any type of liquid, and you can push this bulb down to let the liquid out, so you can essentially control the amount of liquid contained in the pipette.With the burettte, you open the tap to let the liquid out and close it if you want to stop. However you can't really control the amount of liquid in it, if you let more liquid out, you would have to put more back and open the tap to you get what you want.Pipette is more accurate.
(based on Yahoo! Answers)