Q.In the past when people wanted to check the beach for waves what whould they do?
A.They'd go down to the beach and check for waves.
your wasting your time, (and your money) If you've never heard of MagicSeaWeed or WindGuru before now.
These websites give you an understanding on what the waves will be like for today and 6 days on. They give you information like Wave hight in m or f depending on which you choose to use. The only real difference between the two sites is that MagicSeaWeed (MSW) is aimed at surfers, and WindGuru (WG) is aimed at wind-surfers, this dosn't mean you have to use WG i your a wind surfer or use MSW if your a surfer. In fact most people I know use WindGuru, and most people I know are Surfers (not wind Surfers.)
Another Difference is that WG gathers more info for you, whilst MSW gives you an over all score and little other info. Niether arn't usualy wrong.
The moral of the post is: Don't live in the past (we have cool gizmos and gadgets)