Isometric Projection

A form of Axonometric Projection in which the scale of all three axes is the same.  The term “isometric” comes from the Greek for “equal measure.” In true Isometric Projection, No facet is foreshortened more than others, so that all faces of an isometric cube, for example, would have equal surface area in the resulting illustration.

In video games, true Isometric Projection is rarely used, and the term is often used to refer to Dimetric Projection, in which two axes are equal, but a third is foreshortened to a greater extent.

[wikipedia: Isometric Projection]