DEFINITIONS:

A TILING (or TESSELATION or MOSAIC) is a pattern that uses repeated closed shapes to cover a plane, with no gaps or overlaps.

A MONOHEDRAL tiling uses only one shape (though it can be in different positions, including flipped over).

A POLYGON is a figure made up of straight sides .

A REGULAR polygon has all of its sides equal and all of its angles equal

An EDGE-TO-EDGE tiling is one made up of polygons which share whole edges

A REGULAR tiling is a monohedral edge-to-edge tiling using a regular polygon.