hi can any 1 tell me wot shutter speeds mean ?

i no its how long it take from clicking the button to getting a pic but unsure of wot speeds are faster ie

1/2-1/1500

or
8/1/2000

im looking at this 1 and just didnt no if it was worth the money

http://www.steves-digicams.com/2005_reviews/6340z.html

at the moment mine is crap and the shutter speed is

1/4-1/2000 sec

any help would be good