Contents
	What is leather? Forms of leather Types of leather used for coats and jackets Other types of leather
What is leather?
	Leather is a material created through the tanning of hides, pelts and skins of animals, primarily cows. Leather was a very important clothing material, and its other uses were legion. Together with wood, leather formed the basis of much ancient technology. Leather with the fur still attached is simply called fur.
Forms of leather
	Vegetable-tanned leather is tanned using tannin (hence the name "tanning") and other ingredients found in vegetable matter, tree bark, and other such sources. It is supple and brown in color, with the exact shade depending on the mix of chemicals and the color of the flesh. Vegetable-tanned leather is not stable in water; it tends to discolor, and if left to soak and then dry it will shrink and become less supple and harder. In hot water, it will shrink drastically and plasticize, becoming rigid and eventually becoming brittle. Vegetable-tanned leather—can be oiled to improve its water resistance. This supplements the natural oils remaining in the leather itself, which can be washed out through repeated exposure to water. Frequent oiling of leather, with mink oil, neatsfoot oil or a similar material, keeps it supple and improves its lifespan dramatically.
	Alum-tanned leather is tanned using aluminum salts mixed with a variety of binders and protein sources, such as flour, egg yolk, etc. Purists argue that alum-tanned leather is technically "tawed" and not tanned, as the resulting material will rot in water. Very light shades of leather are possible using this process, but the resulting material is not as supple as vegetable-tanned leather.
	Rawhide is made by scraping the skin thin, soaking it in lime, and then stretching it while it dries. Like alum-tanning, rawhide is not technically "leather", but is usually lumped in with the other forms. Rawhide is stiffer and more brittle than other forms of leather, and is primarily found in uses such as drum heads where it does not need to flex significantly; it is also cut up into cords for use in lacing or stitching, or for making dog toys.
	Boiled leather is a hide product (vegetable-tanned leather) that has been hardened by being immersed in hot water, or in boiled wax or similar substances. Historically, it was used as armour due to its hardness and light weight, but it has also been used for book binding.
	Chrome-tanned leather, invented in 1858, is tanned using chromium sulfate and other salts of chromium. It is more supple and pliable than vegetable-tanned leather, and does not discolor or lose shape as drastically in water as vegetable-tanned. More esoteric colors are possible using chrome tanning.
	Buck leathers are exceptionaly absorbent of water. They are made by a labor-intensive process which uses emulsified oils (often those of animal brains) and which has not been industralized. They are known for their exceptional softness and their ability to be washed
Types of leather used for coats and jackets
Glazed leather is usually processed using pressurized glass or steel rollers, the leather's surface is polished to a high luster. It is a vegetable or chrome tanned leather having a bright, smooth, glossy or glass-like grain finish obtained, according to the type of leather, by glazing, plating, ironing, or polishing. Nappa leather, is extremely soft and supple, and is commonly found in higher quality wallets, toiletry kits, and other personal leather goods. Buckskin is a tawing process that uses fatty materials to alter the leather. The resulting supple suede-like hide is usually smoked heavily to prevent it from rotting. Nubuck (or Buff Nubuck) is a full grain leather where the outer surface of the leather has a finely sanded, texturised finish, which gives the boot an added appeal. Nubuck is a full quality leather and should not be confused with suede. Suede is an interior split of the hide. It is "fuzzy" on both sides. Suede is less durable than top-grain. Suede is cheaper because many pieces of suede can be split from a single thickness of hide, whereas only one piece of top-grain can be made. However, as the look of full-grain is in demand, manufacturers use a variety of techniques to make suede appear to be full-grain. For example, in one process, glue is mixed with one side of the suede, which is then pressed through rollers; these flatten and even out one side of the material, giving it the smooth appearance of full-grain.
Other types of leather
	Full-Grain leather, made from the finest raw material, are clean natural hides which have not been sanded to remove imperfections. Only the hair has been removed. The grain remains in its natural state which will allow the best fiber strength, resulting in greater durability. The natural grain also has natural breathability, resulting in greater comfort. The natural Full-Grain surface will wear better than other leather. Rather than wearing out, it will develop a natural "Patina" and grow more beautiful over time. The finest furniture, and footwear, are made from Full Grain leather.
	Corrected-Grain Leather (also called "top-grain leather"). Corrected Leather is fuzzy on one side and smooth on the other. The smooth side is the side where the hair and natural grain used to be. The hides, which are made from inferior quality raw materials, have all of the natural grain sanded off, and an artificial grain applied. Top grain leather generally must be heavily painted to cover up the sanding and stamping process.
	Patent leather is leather that has been given a high gloss finish. The original process was developed in Newark, New Jersey by inventor Seth Boyden in 1818. Modern patent leather usually has a plastic coating
	Shagreen is a rough and grainy type of untanned leather, formerly made from a horse's back, or that of a wild ass, and typically dyed green. Shagreen is now commonly made of the skins of sharks and rays.
	Belting leather is a full grain leather that was originally used in driving pulley belts and other machinery. It is often found on the surface of briefcases, portfolios, and wallets, and can be identified by its thick, firm feel and smooth finish. Belting leather is the only kind of leather used in luxury products that can retain its shape without the need for a separate frame; it is generally a heavy weight of full-grain, vegetable-tanned leather.

Original information from wikipedia.org