What is the difference between death camps and labor camps?

Although the British are said to have invented and used concentration camps in the Boer War, such camps are mainly associated with Nazi Germany.

The Nazis had four main types of camp:
The Stalags: prisoner-of-war camps
Labour camps: where slave labourers were housed
Concentration camps: interim holding camps
Extermination camps; where prisoners were murdered soon after arrival.

Some concentration camps also has extermination facilities such as gas chambers and incinerators.

British and Allied POWs were treated relatively well.
Russian and East European POWs were treated very badly, often being starved or murdered.
Slave labourers were treated sufficiently well to keep them useful to the Nazi state, but such workers did not last long before they became infirm and were shipped off for extermination.
In concentration camps, conditions were hell on earth.
In extermination camps, the poor victims did not have long to suffer before they were killed.