A winch, or power winch, is an extremely powerful vehicle recovery and utility device. They are capable of pulling multiple tons of weight, usually for the purpose of extracting a vehicle from mud or some other trap. Power winches are much faster and stronger than other devices for recovering a vehicle such as a come-a-long.
Winches, while extremely useful, are also very dangerous. They exert a tremendous force which can snap their cable; if said cable is metal(as opposed to synthetic rope) it may flail with enough force to cause serious bodily harm.
Choosing a Winch
There are many factors to consider when choosing a winch, here are a few.
The weight capacity of a winch is the primary factor in choosing a winch. One common rule of thumb is to have a winch that can pull 1.5 times your vehicle weight or more, because if you get stuck you will have to pull the weight of the vehicle AND overcome the resistance of whatever you are stuck on.
Cables and Rope
Most winches come with steel cables, steel is strong, durable, and inexpensive, but more vulnerable to rust and also far more dangerous if they break. Synthetic rope can be purchased and put on a winch after-market, if is lighter, easier to work with, and safer than steel cable, but will be more expensive.
There are many different accessories you can purchase for you winch, some more valuable than others.
Snatch blocks are essentially just big, heavy-duty pulleys. They are used to either redirect a winch cable, or increase its pulling power.