leggings    The term "legging" may be a little confusing one for those better versed in clothing history. Leggings have been around for quite a while: heck, native Indians used to wear leggings, and soldiers too in the first and second World Wars.
Those leggings were a two piece garment though, one for each leg, so let's make this clear from the beginning:

despite the similar names, they had nothing to do with modern leggings whatsoever. Leggings, as we know them today, in the form of second-skin trousers were only made possible by the discovery of spandex. The first modern leggings appeared in the 60s and they were made with cotton and spandex. These leggings weren't all that different from the ones worn by men for warmth in the winter, only women's versions were decorated with different patterns.
The heyday of the leggings started in the 1980s when the shiny nylon-lycra leggings, previously confined to the gym and to various sporting activities, made the jump to mainstream fashion.

These leggings are made with a combination of nylon and spandex. Nylon usually makes up 80-90% of the mix (the more nylon there is, the shinier the leggings are), while spandex accounts for 20-10% of the composition. The great thing about shiny nylon lycra leggings is that they give the wearer’s legs the same shiny-glossy finish as pantyhose, but in the same time they don’t let any skin show through and they never run a seam.

red leggingred legging Due to their texture, shiny nylon leggings have gained great following among hosiery enthusiasts. Black ones have always been among the most popular, but all colors (including neon ones) are worn. Nylon lycra leggings and neon colors represent a clue to the garment’s origins. When they first became commercially available in the early 80s (possibly late 70s), shiny lycra leggings were almost exclusively used for biking and for the gym. The shiny bright-colored panels were meant to draw attention, thus making the wearer easier to notice for motorists. As the shiny nylon-legging craze reached new peaks though, more and more styles and patterns were used. Shiny lycra really didn’t set any kind of limits on this tendency. Some styles included nylon lace panels combined with the base nylon-spandex material. Other manufacturers used patterns in the shiny nylon-lycra material they used. There were leggings made of ribbed lycra (shiny nylon-spandex fabric which had 3-d stripes) or material with rectangular 3-d patterns.
During the 80s, shiny leggings previously only used for exercising made the jump to street fashion. Young girls everywhere wore them with long T-shirts (and sometimes even short ones), in some parts of the world well into the 90s.
Then, as quickly as they shot to the top, shiny leggings and the wacky speck of color they brought to the fashion world were gone, off the fashion-radar. Such 80s style leggings can still be found in certain shops, online or in thrift-shops.
leggings2005 was the year of resurgence for the shiny leggings (we just knew it: they were too hot to disappear without a trace forever), although this time around, they surfaced in a somewhat different form. These new leggings are made of a material which looks like latex. Metallics are truly metallic these days (we’re talking T-1000 metallic), and generally speaking, leggings have a different kind of sheen to them. leggings They’re latex-like or wet-like mostly. Gone are the wacky colors and patterns of the 80-90s, as most of the leggings worn today span a significantly toned-down range of colors.

As far as legging-styles go, they can only really be classified based on their length on the wearer's leg. There are full-length ones and Capri-length ones (which are only about mid-calf long). Based on design, the number of achievable styles is quite limitless. Some leggings have lace panels (on the bottom or up the length of the leg even), some are sheer (pantyhose-like), some have tears in them, others are shredded, still others include metallic elements in their designs. The new (2005 and onward) legging trend has been fully embraced by celebrities. Rihanna, Demi Lovato and Lindsay Lohan are some of the best known celebrities to don shiny leggings. American Apparel is quite probably the best known maker of such shiny leggings, but Kova and T and Members Only are popular manufacturers as well.

Jeggings (a combination-word from legging and jeans) represent the newest legging-trend. These leggings basically imitate the way jeans look. Some of these jeggings have faux pockets and a colored seam down the length of the leg.