Nested for Loops:

The action of a loop can be any of the valid statement(s). Whenever the action of a loop is the other loop, this is known as nested loop.

As an illustration, a nested for loop will be elaborated in a script which will print a box of *'s. The variables in the script will identify how many rows and columns to print. For illustration, if rows have the value 3, and columns have the value 5, the output would be:

*****

*****

*****

As the lines of output are controlled by printing the newline character, the fundamental algorithm is:

For every row of output,

- Print the needed number of *'s

- Shift the cursor down to the next line (print the '\n')