An assortment of sweets, generally aimed at annoying little children and usually to be found in high-street shops such as Woolworths, where masses of the things can be found in huge plastic containers. The idea is to scoop out a few of each and put them in a little bag, then take the bag to the till and pay for it by weight.
The sweets are usually in bright, artificial colours and are highly likely to make you sick. They're also pretty easy to steal; most people I know have stolen at least the one. I suppose you could say they're a haven for trainee shoplifters.