Sliced fish is put to dry on the open air on a beach beside Negombo.
Fresh fish rapidly deteriorates unless some way can be found to preserve it. Drying is a method of food preservation that works by removing water from the food, which inhibits the growth of microorganisms. Open air drying using sun and wind has been practiced since ancient times to preserve food. Water is usually removed by evaporation (air drying, sun drying, smoking or wind drying) but, in the case of freeze-drying, food is first frozen and then the water is removed by sublimation. Bacteria, yeasts and molds need the water in the food to grow, and drying effectively prevents them from surviving in the food.Fish are preserved through such traditional methods as drying, smoking and salting.The oldest traditional way of preserving fish was to let the wind and sun dry it. Drying food is the world's oldest known preservation method, and dried fish has a storage life of several years. The method is cheap and effective in suitable climates; the work can be done by the fisherman and family, and the resulting product is easily transported to market.Stockfish is unsalted fish, especially cod, dried by cold air and wind on wooden racks on the foreshore. The drying racks are known as fish flakes. Cod is the most common fish used in stockfish production, though other whitefish, such as pollock, haddock, ling and tusk, are also used.Over the centuries, several variants of dried fish have evolved. Stockfish, dried as fresh fish and not salted, is often confused with clipfish, where the fish is salted before drying. After 2–3 weeks in salt the fish has saltmatured, and is transformed from wet salted fish to Clipfish through a drying process. The salted fish was earlier dried on rocks (clips) on the foreshore. The production method of Clipfish (or Bacalhau in Portuguese) was developed by the Portuguese who first mined salt near the brackish water of Aveiro, and brought it to Newfoundland where cod was available in massive quantities. (q.v.). Salting was not economically feasible until the 17th century, when cheap salt from southern Europe became available to the maritime nations of northern Europe.
Stockfish is cured in a process called fermentation where cold adapted bacteria matures the fish, similar to the maturing process of cheese. Clipfish is processed in a chemically curing process called saltmaturing, similar to the maturing processes of other saltmatured products like the Parma ham.Bacalhau is the Portuguese word for codfish and in a culinary context refers to dried and salted codfish. Fresh (unsalted) cod is referred to as bacalhau fresco (fresh cod). Bacalhau dishes are common in Portugal and Galicia, in the northwest of Spain, and to a lesser extent in former Portuguese colonies like Angola, Macau, and Brazil. There are said to be over 1000 recipes in Portugal alone and it can be considered the iconic ingredient of Portuguese cuisine (but curiously the only fish that is not consumed fresh in this fish-loving nation). It is often cooked on social occasions and is the Portuguese traditional Christmas dinner in some parts of Portugal.

Mackerel (Sukho Bangdo in Konkani language) is dried in Goa since ancient times. If preserved well they can stay for many years. Prawn and shark are also dried in Goa.

Baccalà (in Venetian Language: bacalà) is sun-dried stockfish, rather than salt cod. In other parts of Italy dishes made with salt cod are given the same name. Baccalà dishes made with stockfish are soaked for several days to soften the fish. Salt cod, which is already soft, is also soaked to remove excess salt.

Balyk is the Russian term for the salted and dried soft parts of fish of large valuable species, such as sturgeon or salmon. Over time, the term has come to apply also to smoked fish of these species.

Boknafisk is a variant of stockfish and is unsalted fish partially dried by sun and wind on drying flakes or on a wall. The most common fish used for boknafisk is cod, but other types of fish can also be used. If herring is used, the dish is called boknasild.

Daing (also known as Bulad or Tuyô) refers to sun-dried fish in the Philippines. Almost any kind of fish is used, but the most popular variant uses rabbitfish (locally known as danggit). Cuttlefish and squid may also dried this way. The amount of drying can vary. In the labtingaw variant, the drying period only lasts a few hours, allowing the fish to retain some moisture and texture.[5] In the lamayo variant, the fish isn't dried at all, but simply marinated in vinegar, garlic and spices.
Dried squid
Fesikh is a traditional Egyptian fish dish consisting of fermented salted and dried gray mullet, of the mugil family, a saltwater fish that lives in both the Mediterranean and the Red Seas.[ he traditional process of preparing it is to dry the fish in the sun before preserving it in salt.(Wikipedia)