Knockdown texture is a drywall texture that gets its name from the process that is used to make it. Knockdown is made by watering down drywall mud/joint compound to the approprieate consistency and then spraying the joint compound on the wall. When the joint compound is sprayed on the wall it creates small raised bumps. The joint compound that was sprayed on the wall is then allowed to dry for a short period, which causes the top surface area of the joint compound to dry out. A large, plastic, drywall knife is then run over the surface where the joint compound was sprayed and then the top surface area of the raised bumps is "knocked down." This causes the textured area to look like there is a lot of raised surface area on the face of the drywall, which gives depth and variation to the completed work.