Cheese is a kind of food derived from milk. It can produce a variety of flavors, textures and forms through the condensation of milk protein casein. It contains protein and fat in milk, usually cow, buffalo, goat or sheep's milk. In the production process, milk is usually acidified, and the addition of rennet will cause coagulation. Separate solids and press to final form. Some cheeses have mold on the skin or on the whole surface. Most cheese melts at cooking temperature.

Hundreds of cheeses from different countries have been produced. Their style, texture and flavor depend on the source of milk (including animal diet), pasteurization, butter content, bacteria and mold, processing and aging. Herbs, spices or wood smoke can be used as flavoring. Many cheeses, such as red Leicester, are made from yellow to red by the addition of annatto. Other ingredients may be added to some cheeses, such as black pepper, garlic, chives or cranberries.

For some cheeses, milk is condensed by adding acid (such as vinegar or lemon juice). Most cheese is acidified to a lesser degree by bacteria that turn milk sugar into lactic acid, which can then be coagulated by adding rennet. A vegetarian alternative to rennet is available; most are produced by the fermentation of the fungus Mucor miehei, but others are extracted from various species of the Cynara thistle family. Cheese makers in the vicinity of dairy areas may benefit from fresh, low-cost milk and lower transportation costs.

Cheese is valued for its portability, long life and high content of fat, protein, calcium and phosphorus. Cheese is denser than milk and has a longer shelf life than milk, although how long cheese will remain depends on the type of cheese. The label on the cheese package usually states that the cheese should be eaten within three to five days after opening. Generally speaking, hard cheese (such as parmesan cheese) has a longer service life than soft cheese (such as brie or goat cheese). Some cheeses have a long service life, especially when packaged in a protective peel, and can be sold in a favorable market.

There are some controversies about the best way to store cheese, but some experts say wrapping it in cheese paper can provide the best results. The inside of the cheese paper is coated with porous plastic and the outside is covered with wax. This particular combination of internal plastic and external wax protects the cheese by allowing the condensate core on the cheese to be sucked away while preventing moisture from escaping from the cheese.