Survivalism is a movement of individuals or groups (called survivalists or preppers) who actively prepare for emergencies, including possible disruptions in social or political order, on scales from local to international. Survivalism also encompasses preparation for personal emergencies, such as job loss or being stranded in the wild or under adverse weather conditions. The emphasis is on self-reliance, stockpiling supplies, and gaining survival knowledge and skills. Survivalists often acquire emergency medical and self-defense training, stockpile food and water, prepare to become self-sufficient, and build structures such as survival retreats or underground shelters that may help them survive a catastrophe.
The kind of gear you need – It’s easy to get obsessed with survival gear and start accumulating every new product that comes on the market. If you have money to burn and engage in a variety of backcountry activities this might be a sound strategy. Most people however decide pretty early on what type of outdoor activity floats their particular boat and as such any survival gear should have some sort of relationship to that activity. Everyone, for instance, should have an emergency whistle with them but not everyone will need an extreme sleeping bag. Everyone will need first aid items but not everyone will need to carry croval shovel or a tactical watch or field watch. If you’re a mountaineer you’ll probably want that shovel, especially if you’re climbing in the winter. If you’re going on a day hike and aren’t bringing food that requires preparation there’s no need for a mess kit and so on.
Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.