With luck, you'll never find yourself alone, far from civilisation, faced with the task of ensuring your own survival. If you do, this 1950s training video from the US Navy has some valuable tips and tricks to help you find safe food and water, build shelter, and take care of yourself.
It's long, but it's full of useful information. Despite being severely dated, the video still offers a wealth of useful information on edible plants and animals, how to build snare traps and dress game, and then prepare them properly for consumption.
The focus of the video is on the temperate regions of the northern hemisphere, including the US and Canada, northern Europe, and Russia. There are plenty of tips that are applicable anywhere, however -- and it's an interesting historical insight if nothing else.