A hair weave is a very general term used to describe human or artificial hair used to alter one's natural hair appearance by adding additional hair to one's natural hair or by covering the natural hair altogether with human or synthetic hair pieces.
The highest-quality extension hair is Indian human remy hair. Remy hair still possesses the cuticle layer, which is the outermost part of the hair strand; it resembles shingles on a roof. All remy hair has the cuticle layer of the hair flowing in the same direction, flowing the way it would naturally.
The cuticle layer is important when concerned with hair tangling, longevity of the use(up to one year), and how well the hair shines. When the cuticle layer is intact and lying flat, the hair is capable of reflecting light, so that the hair shines.
Some of the benefits of hair weaves are that they can lengthen hair, add volume and/or thickness to fine or thinning hair, and add fashion colors to natural hair without the damage of chemicals. The process of adding colors to natural hair is usually done with strand-by-strand extension systems.
One type of application is called a sew-in. Weft hair can also be applied by gluing directly to the natural hair using hair glue specifically made for hair weaves. The glue can be easily washed out using a special shampoo/conditioner that will remove the glue without removing the real hair. A special glue remover may also be used.
Extension hair refers to the weave hair being applied strand by strand rather than in long, sewn-together rows. Strand-by-strand hair has approximately 50-80 strands attached by keratin tips resembling the end of a shoe string. These can then be attached by bonding directly to the hair or using copper links, which provides the most natural look.
The method is the most time-consuming, as between 100 to 300 individual extensions are applied. The amount of time necessary makes this type of application a more expensive service than other options. Other types of extensions include ponytails or ponytail pieces. Just like any wig or wigpiece, the colors for hair to be weaved can range from "realistic" colors, such as red, black, brown, and blonde, to colors such as pink, blue, green, and purple.
Original source: http://en.wikipedia.org/wiki/Hair_weave
Hair Weave - Adding Additional hair to Natural Hair
