Grading in civil engineering and landscape architectural construction is the work of ensuring a level base, or one with a specified slope, for a construction work such as a foundation, the base course for a road or a railway, or landscape and garden improvements, or surface drainage. The earthworks created for such a purpose are often called the sub-grade or finished contouring (see diagram).
Grading (engineering) Wikipedia
In the case of gravel roads and earthworks for certain purposes, grading forms not just the base but the cover and surface of the finished construction, and is often called finished grade.
It is often done using heavy machinery like bulldozers and excavators to roughly prepare an area and then using a grader for a finer finish.
In the environmental design professions grading and regrading are a specifications and construction component in landscape design, landscape architecture, and architecture projects. It is used for buildings or outdoor amenities regarding foundations and footings, slope terracing and stabilizing, aesthetic contouring, and directing surface runoff drainage of stormwater and domestic/irrigation runoff flows.