The most common ... almost universal ... way is to identify the location using modified spherical coordinates such as 'latitude' and 'longitude'.
The 'latitude' of a place is its angle north or south of the equator on the spherical surface.
The 'longitude' of a place is its angle east or west of the line on the spherical surface that joins the poles of rotation and passes through a scratch on the floor of the Royal Observatory in Greenwich, England.