Fruit preserves are fruits, or vegetables, that have been prepared and canned for long term storage. The preparation of fruit preserves traditionally involves the use of pectin as a gelling agent, although sugar or honey may be used as well. The ingredients used and how they are prepared will determine the type of preserves; jams, jellies and marmalades are all examples of different styles of fruit preserves that vary based upon the ingredients used. Jam contains both fruit juice and pieces of the fruit's (or vegetable's) flesh, however some cookbooks define jam as cooked and gelled fruit (or vegetable) purees.

Properly, the term jam refers to a product made with whole fruit, cut into pieces or crushed. The fruit is heated with water and sugar to activate the pectin in the fruit. The mixture is then put into containers.