Although it is a little past time to be putting up food for the winter, I’ll finish with preserving food. Canning is probably the least desirable way to preserve your harvest. It requires a lot of special equipment and if you don’t do it right you can even get food poisoning. Nutrient-wise it usually has less nutritional value than either drying or freezing. For many this is still their preferred method.
First thing is, you have to have special jars and lids. You need to prepare the food in a certain manner and seal the jars so no air is inside to cause spoilage. For most foods I would choose one of the other two methods already discussed, but in the case of jams, jellies, syrup, and pickles or relishes, this is the only way to go. With sugary foods you can often just seal them with wax, rather than having to do a whole hot water bath.
Last is cold storage. Most people cannot do this, because they don’t have a proper space. Some people have garages or out buildings that will maintain a safe temperature. If so, learning how to layer and store root crops and fall fruits such as apples and pears would really be worth the effort. Even green tomatoes can be held in cold storage for a long period and then brought in to ripen. The National Gardening Association has some basics about cold storage.