Have you ever been in a situation that you only have canned food and nowhere around a can opener? If so, this video is made for you. Even if you have not been in such situation, you might need to know the technique. All you have to do is to find a rough piece of concrete or large flat rock or similar surface. If you try to open bigger can it will take you more time to open it, but the procedure is the same. This is a cool technique and it is a great survival tip that you need to learn and can come handy in difficult situations. This is from reliable source, Russian zombie apocalypse survivalists. I hope you liked it and you might need it.
NOTE: Be cautious, because when you open the can, the edges will be sharp as knife. Be careful not to cut yourself.
Using any method that does not involve proper can opener is risky because it can get metal slivers in the food contents, so be careful before consuming the content of the can.