In the specific case of the code example from the original question, the
System.out.print("\n");
is there to move to a new line between incrementing i.
So the first print statement prints all of the elements of Grid[0][j]. When the innermost for loop has completed, the "\n" gets printed and then all of the elements of Grid[1][j] are printed on the next line, and this is repeated until you have a 10x10 grid of the elements of the 2-dimensional array, Grid.
