In this example we are going to print the multiplication table up to 10.

#!/usr/bin/env python
i = 1
print "-" * 50
while i < 11:
    n = 1
    while n <= 10:
        print "%4d" % (i * n),
        n += 1
    print ""
    i += 1
print "-" * 50

The output

[kd@kdlappy book]$ ./multiplication.py
--------------------------------------------------
   1    2    3    4    5    6    7    8    9   10
   2    4    6    8   10   12   14   16   18   20
   3    6    9   12   15   18   21   24   27   30
   4    8   12   16   20   24   28   32   36   40
   5   10   15   20   25   30   35   40   45   50
   6   12   18   24   30   36   42   48   54   60
   7   14   21   28   35   42   49   56   63   70
   8   16   24   32   40   48   56   64   72   80
   9   18   27   36   45   54   63   72   81   90
  10   20   30   40   50   60   70   80   90  100
--------------------------------------------------

Here we used one while loop inside another loop, this is known as nested looping. You can also see one interesting statement here

print "-" * 50

In a print statement if we multiply the string with an integer n , the string will be printed nmany times. Some examples

>>> print "*" * 10
**********
>>> print "#" * 20
####################
>>> print "--" * 20
----------------------------------------
>>> print "-" * 40
----------------------------------------