Your freezer isn't a miracle machine, though. To keep food in good condition for a long time you need to follow a few simple rules. Get it wrong and you're likely to find your food deteriorating – and maybe even unsafe to eat.
Some general recommendations for freezer storage are:
To safely store food for long periods of time, use a deep freezer that will keep the temperature at 0ºF or lower. It's also a good idea to buy a freezer thermometer and check the temperature frequently.
Keep the freezer as full as possible. A half-empty freezer will spill cold air every time the door is opened, letting warm air in. It has to cool that down once the door is closed again. In a full freezer there's less space for warm air to take up. If there's a lot of empty space in yours, put in empty cardboard boxes – they'll help keep cold air inside. If you have a chest freezer this isn't a problem, because the denser cold air will stay inside when you open the lid.
Don't load a lot of food into your freezer at once. That will overload the freezer's cooling capacity, and raise the temperature inside. It will also take longer to freeze the food you just put in, and slow freezing reduces the quality of food. Don't put in more than three pounds per cubic foot of freezer space every day.