Face loop selections let you select several faces across a polygon mesh without having to select each face individually.
To select a face loop on a polygonal mesh
All the faces along the same line are selected.
To select a partial face loop on a polygonal mesh
All the faces between the two faces are selected.
You can re-use faces from previous loop selections as the first selected face of another loop selection. You can use this technique to select multi-directional face loops.