Sheetrock is also known as gypsum board, gypsum panel, plasterboard, buster board, and custardboard. In laymen's terms, they all mean drywall! Drywall is much like an oreo, where the inside is gypsum and the walls are thick backer paper. Sheetrock is the most commonly used material for interior construction of walls and ceilings because of how inexpensive and multifaceted it is. Chemical additives can be added to the gypsum to make it water resistant. In addition, dyrwall can be manufactured to be thicker for better durability and fire resistance (Type X drywall). Soundproof drywall is manufactured for offices or homes near high levels of noise pollution. However, such alterations to standard gypsum board drywall increases the price. There exist many names for drywall because of how many different types there are and because of how simple its composition is. You can imagine its name buster board comes from how fragile it can be!
There are many types of drywall textures, each with their own aesthetic appeal. The most commonly known texture is the popcorn texture, which use to be in style in the 80's. It gets its name for its sporadically placed rounded bubbles that appear similar to popcorn. This was commonly seen on ceilings. Another well know drywall texture is the organe peel texture. Like the popcorn texture, it features slightly raised bumps and skids that resemble the inside of an orange peel. This texture can be replicated to have smaller bumps or bigger ones. A less commonly used texture in the average home is the comb drywall texture. A brush is used to make rainbow like arches that are patterned evenly across the wall. Finally, there is the stomp brush drywall texture that, to your great surprise, uses a brush to create. Walls with this textures seem to have little vein-like plaster mountains on it.