If you pop out into space, you die. No oxygen to breathe, no ambient pressure makes your bodily fluids boil, UV radiation burns your skin to a crisp. It's not a good place to be for humans. So in order to survive, you need to bring a number of things along, commonly called the "life support system". This talk explains how this works!
How do oxygen generators and CO_2 scrubbers work? Do you need to heat or cool your craft? If you eat beans and fart a lot, do you ever get rid of the smell? Can you just fill your spacecraft with plants and live off them?
This talk goes through historic, present and future ways that life support is managed in spacecraft, spacesuits and future planetary outposts. It also explains why you have to breathe your own pee on the International Space Station.
(This is the logical followup to the two previous, german talks about how to fly spaceships and how to build them, from the GulaschProgrammierNacht 13 and 16)
Slides: http://urs.nerd2nerd.org/rC3-talk.svg