There is ambiguity and confusion concerning the nomenclature of parallel projection. Today, such representations are often broadly identified as axonometrics. However, the actual history of parallel projection, delineated by oblique and axonometric projections, reveals inherent spatial differences. By clarifying the intrinsic demarcations between these two forms of parallel projection, one may bring into question anew the approaches and applications of parallel projection as an architectural form of representation in the twentieth and twenty-first centuries.