Peckham is a part of the London Borough of Southwark, located mostly south of the Old Kent Road, which historically developed from a satellite village of London into a fairly respectable working class district into its current state of one of the worst residential areas of London (and possibly even Western Europe).
Massive council housing developments were at first welcomed by people being rehoused in them after the WW2 damage and the slum clearance program, but with time the housing fabric has deteriorated and the industrial and port jobs have disappeared.
Nowadays Peckham housing fabric has undergone some regeneration but the area remains an archetypal sink estate, with high levels of deprivation, crime and gang violence; one of the (not that many for such a large city) districts in London which might not be safe to visit even in broad daylight, although there is gentrification creeping in from the south.
And yet, Peckham is not entirely without tourist interest. Those interested in modern architecture might want a look at the award-winning Peckham Library while one of the best London art spaces and a must for those who follow the fashionable art scene, the South London Gallery, is located on Peckham Road in the nearby Camberwell.
Camberwell, also in the Southwark borough, is also poor, also heavily built up, but it has some nice Georgian houses as well as all the misguided post-war concrete blocks and in addition to the aforementioned South London Gallery it also boasts an art college and a major teaching hospital, so artists and students bring lively, edgy buzz to the area that gets a showcase in the annual Camberwell Arts Festival.
For many years now Camberwell has been hailed as a bit of up-and-coming area, and although hasn't quite (at least to my knowledge) upped and came yet, the local inhabitants include artists, musicians, journalists and others looking for an edgy-but-civilised inner city location.