The age old question of somebody who wants to learn music but doesn't know which instruments to learn, until they hear someone play the piano or the guitar and some ladies (or even guys) stare at that person playing the instrument like he was a star! Well, that isn't a good reason to begin learning something but hey, that's not the topic. So, which is harder to learn? Well, base on my experience and my experience alone, the guitar is harder to learn.

Why you say? Well, if it's your first time, it will take weeks before your hands will be able to grow skin thick enough to make you immune to the feeling of pain that the guitar strings will inflict. However, it really depends which you take on first. The piano was much easier for me because I liked the way it sounded, even though I obviously didn't know what I was doing the first time I touched a piano. Basically, It all comes down to what pleases you more. They are both hard to learn and will take some practice and sacrifice on your part, but if you like what you're hearing (even though sounds like a cat screaming in agony to others) then it will keep you motivated.