Create Histogram from Data

I have a 2D array X and I want to plot it as a histogram. Each element X(i,j) should coresspond to a box. I have a 20x20 2D Array, so if I would do it by hand I had to create 400 boxes by hand and justify the height of each individual. Furthermore, I have a lot of other 2D arrays that I want to plot this way. Is this possible withouth editing each box on its own?