LCD panels are made of two layers of a glass-like material, which are polarized, and are "glued" together. One of the layers is coated with a special polymer that holds the individual liquid crystals. Electric current is then passed through individual crystals, which allow the crystals to pass or block light to create images.
LCD crystals do not produce their own light, so an external light source, such as florescent bulb is needed for the image created by the LCD to become visible to the viewer.
LCD televisions can be made very thin, thus allowing them to hung on a wall or placed on small stand on top of a table, desk, dresser, or cabinet very easily.
In addition, with some modification, LCD technology is also used in video projectors.
For a closer look at LCD Flat Panel Television, check out my Guide to LCD Television.