👉 Caulking is a type of sealant that is used to fill cracks, holes and other imperfections in surfaces. It is typically applied to concrete, brick or other hard materials by applying a thin layer of adhesive compound onto the surface and then allowing it to cure for several weeks before using the surface again. Caulking can be applied with a variety of methods depending on the type of material being sealed, but it is commonly used in areas where there are cracks or defects that need to be filled