The value `NaN`

means Not-A-Number.
This value is obtained when you try to do
mathematical operations not with numbers,
but with something else.
For example, an attempt to multiply a string
by a number will give such a value:

`alert('abc' * 3); // shows NaN`

Any operations with `NaN`

still lead to
the `NaN`

result:

`alert(NaN + 1); // shows NaN`

Make two strings. Multiply them over each other. Print the result of the multiplication on the screen.