The West Texas Intermediate is, together with Brent Crude, one of the most important western oil. It is usually called light and sweet, because of its low density and low sulphur (less than 0.5%) concentration. The amount of the API gravity is 39.6 and the specific gravity 0.827.
Rather Brent Crude, WTI has its source in the Midwest and Gulf Coast regions in the United States. The refining process goes within the country, which means a big advantages for the US market. As well as Brent, this American oil is also processed to gasoline and high quality fuel.
WTI and Brent crude are those two oil types, which price rates are mostly on every blog or page traced. As said in the LCO article, the sweet light oil is that, which gives two-thirds of the most traded types.
The price of WTI is often lower, than Brents. Of course, it depends on the rate of the US dollar. The actual value approaches the $100, although it's slowly decreasing.