Ah....... never did understand that whole thing.
In the Uk, colleges are essentially a 'lower' tier than universities; they offer shorter length diplomas, etc - essentially can be used as a stepping stone to university or for a non-degree based qualification.
Basically the Uk goes something like;
7 years of primary school (I believe the Us kindergarten + grade school is equivalent); roughly ages 5-12
6 years of secondary school (can leave after 4th year, though; 3rd+4th years are spent earning 'standard grade' qualifications, 5th is 'Higher' and 6th is either higher or Advanced Higher; English names for these qualifications are different, though); roughly ages 12-18
Then, you can go to either University or College. If you go to College, then you can proceed from there into uni (it's a common process to go to college first if you don't have the qualifications for admission to the uni course you want)
NB: Scottish BSc courses are 4 years long, where the last year is the 'honours' segment (which is graded on 3rd, 2:2, 2:1, 1st scale). i think english courses are a year shorter; I presume the honours part is incorporated with their degree qualification or something.
NB2: Actually, i might go back and do a PhD myself.......