Just recently bought an 03 Honda civic ex and when I put my car in reverse it makes a whining sound. Anyone know what this is??

 

coming from where? and what kind of whining sound? Reverse gear is a straight cut gear so it does make more noise then the forward helical cut gears

 

Reverse gearing in the transmission is derived of straight-cut gears. Your forward gearing is derived of helical-cut gears. Straight cut gears always make noise, so its completely normal that you hear whining in reverse.