Words to Numbers

Thanks but I now have another problem!
I am up to the point in where I have made a table and used a VLOOKUP and I can type a word into a cell and it then brings up the allocated number in a different cell.
But I would like it that excel treats the word as a number. For example if I type in the word 'hello' and put an allocated number to it in the table, when I type in the word 'hello' into a cell, when using formulae etc., it treats the word 'hello' as the allocated number.

Sorry for the trouble, thanks!

Oh. . .

Thanks NBVC! This helped a lot