So you'll work from te outside to the inside: every time the 'top' loop will run, that is, 5 times, it will execute the code between the brackets.
In there, there is another loop, using j as index, which will run 10 times. So when we run the upper loop 5 times, and time it executes another loop 10 times, we'll get that this run 50 times. So 50 times, this will print out the product of i and j.
After each 10 loops of the 'j'-loop, it will print out a new line.
