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Tar is a viscous black liquid derived from the destructive distillation of organic matter. Most tar is produced from coal as a byproduct of coke production, but it can also be produced from petroleum, peat or wood.

The use of the word "tar" is frequently a misnomer. Naturally occurring "tar pits" (e.g. the La Brea Tar Pits in Los Angeles) actually contain asphalt, not tar, and are more accurately known as asphalt pits. Tar sand deposits contain bitumen rather than tar, as does the Tar Tunnel in Shropshire. "Rangoon tar", also known as "Burmese Oil" or "Burmese Naphtha", is actually petroleum. In English and French, "tar" means primarily the coal derivative, but in northern Europe, it refers primarily to the wood distillate, which is used in the flavoring of candy (among other things). "Tar" and "pitch" are often used interchangeably; however, pitch is considered more solid while tar is more liquid.

Wood tar is non-poisonous (but microbicidial) and has pleasant oder. Wood tar can be used even as food additive. On the other hand, tar made from coal or petroleum, is considered toxic and carcinogenic because of its high benzene contents. Coal and petroleum tar has pungent or repulsive odour.

Tar is used in treatment of psoriasis, where coal tar is the most effective. Tar is a disinfectant substance, and used as such. Petroleum tar was also used in ancient Egyptian mummification circa 1000 BC.^[1] In archaic Finland wood tar was considered a panacea reputed to heal "even those cut in twain through their midriff". Another Finnish proverb is if sauna, vodka and tar won't help, the disease is fatal. The use of wood tar in traditional Finnish medicine is because of its microbicidial properties.

Tar was a vital component of the first sealed, or "tarmac", roads. It was also used as seal for roofing shingles and to seal the hulls of ships and boats. For millenia wood tar was used to waterproof sails and boats, but today sails made from inherently waterproof synthetic substances have negated the need for sail sealing.

Wood tar is still used to seal traditional wooden boats and the roofs of historical shingle-roofed churches, as well painting exterior walls of log buildings. Wood tar is also available diluted as tar water, which has numerous uses:

• Flavoring for candies (e.g. Terva Leijona) and alcohol (Terva Viina)
• As a spice for food, like meat
• Scent for saunas. Tar water is mixed on water that is turned to steam to the air
• Anti-dandruff agent in shampoo
• As a component of cosmetics

Mixing tar with linseed oil varnish produces tar paint. It has translucent brownish hue, and can be used as saturating and toning the wood and protecting it from weather. The tar paint can also be toned with various pigments, producing translucent colours and preserving the wood texture. Because of its paint-like properties, wet tar should not be touched with bare skin, as it can dry to produce a permanent stain...

The heating (dry distilling) of pine wood causes tar and pitch to drip away from the wood and leave behind charcoal. Birchbark is used to make particularly fine tar (tökötti).

The by-products of tar are turpentine and charcoal. When deciduous tree woods are subjected to destructive distillation the by-products are methanol (wood alcohol) and charcoal.

• Bitumen
• Coal tar
• Pitch (resin)
• Pitch drop experiment
• Tarring and feathering

• ↑  Geotimes - February 2005 - Mummy tar in ancient Egypt. Retrieved on January 9, 2006.

• [2] - details history and uses of "Rangoon Tar".