What is a favela?

I realise I've been throwing around the word 'favela' presuming readers will know what I'm on about. I'll briefly explain here what they are. In short they're the shanty towns in Brazil. I think the first was in Rio, and they have a lot here. They get their name from the favela plant that grew in the location of the first one. They're typically densely populated areas where houses are built very cheaply, and crudely. Rent isn't paid; there are no land deeds. But it's not like the government would do anything because no one has money, and the government is pretty messed up here anyhow (I'll save it's corruption for another post). Where would the people go? So people continually build these small houses, sometimes literally upon each other, and they sit on the steep hillsides. Often there is crime; mostly drug related - which ofcourse brings violence with it. There is some police presence on the outskirts but the police are corrupt too: with little pay themselves, they often find a reason to attempt to arrest someone, accepting bribes to let the falsely accused go. They are armed. Below are some photos of the surrounding favelas where I'm staying. It is pretty safe at the top of them; usually the crime happens further down in the depths. Tom said you can tell which guys are the drug dealers/users because they don't say 'hi' or acknowledge you on passing. Usually locals do, and are very friendly.