Doing roadwork involves a variety of tasks, such as repaving, paving, tarring, and training. Repaving is the process of replacing an existing pavement with a new one, usually involving the removal of the old pavement and the installation of a new layer of asphalt. Paving is the process of laying down a new layer of asphalt on top of an existing surface. Tarring is the process of applying a layer of TAR to a surface in order to protect it from the elements. Finally, training is the process of teaching workers how to properly perform the various tasks involved in roadwork.