Fourier: Basic definition

Greetings.

I seek advise regarding the following sentence as it appears pertaining to the image that appears below:

"[In Discrete Fourier Transform] it is common to express the transform as G(k) instead of G(k/N) in order to simplify the notation, but one should keep in mind that the frequency is the normalized k/N and not the integer k."

http://img200.imageshack.us/img200/8...009105d.th.jpg

I would appreciate assistance with an explanation of what 'normalizing' refers to, and why it is required.

Look forward to a prompt response.

Best regards,

wirefree