LONG division versus SHORT division

Today we learned how to do long division.  Of course I just couldn't figure out what the teacher was doing so I did it my way.  I got the right answer so I was happy.  I just couldn't figure out why he kept putting all the numbers underneath and then adding and multiplying.   He was doing long division (that appears to be a totally closed door to me) and I was doing short division.  I suppose if I was trying to divide some huge number by some equally huge number I wouldn't be able to do it my way.  However, at the moment I will proceed slowly and surely and then get Rosie to show me how to do long division.  I seem to understand better when she shows me.  I want to learn how to do it the right as we have a couple of tests coming up. I gather I should actually do the sum the way I am supposed to.  Why is it that the right way is hard and the easy way gives me the right answer?   Life is a conundrum!