Why read less than ‘good’ (and sometimes downright bad) books? Are they not throw-away literature? ‘Definitions’ argues that, though bestsellers may be ephemeral, they are vivid snapshots of their age. As a category, they are wholly unpredictable as to content and literary quality. America was peculiarly suited for the development of a popular fiction industry. There was no tradition of state control over literature and no commercial control, via privilege or monopoly. Until 1891, the American book trade was not bound by international copyright, which meant books could be sold very cheaply in vast numbers. Discounting boosted sales and was only possible in the UK after the abolition of the Net Book Agreement (NBA).