Khaki is used to refer to any type of khaki colored fabric, although it is most commonly made from cotton or wool.
Khaki has traditionally been used by the armed forces of countries around the world, because its dusty color is perfect for camouflage, especially in desert or dry terrain.
More recently, khaki has grown to be used in khaki pants and other business attire, and has acquired a more formal and conservative feel to it, in contrast to its military origins. As such, khaki is hardly ever found in fashionable mens wear, and guys interested in attraction fashion should generally avoid it outside of the office.
If you are going to wear khaki pants, try wearing khaki pants that are slightly ruffled and have a rougher look to them to avoid the office-worker syndrome. Khaki jackets can also look pretty cool, and the color is perfect matching and layering with other items.