 Irmak (2012) criticizes the dual nature of software proposed by Colburn (1999, 2000). He understands an abstract entity as one lacking spatio-temporal properties, while being concrete means having those properties. Defining software as a concrete abstraction would therefore imply for software to have contradictory properties. Software does have temporal properties: as an object of human creation, it starts to exist at some time once conceived and implemented; and it can cease to exist at a certain subsequent time. Software ceases to exist when all copies are destroyed, their authors die and nobody else remembers the respective algorithms. As an object of human creation, software is an artifact. However, software lacks spatial properties in that it cannot be identified with any concrete realization of it. Destroying all the physical copies of a given software would not imply that a particular software ceases to exist, as stated above, nor, for the very same reason, would deleting all texts implementing the software algorithms in some high-level language. Software is thus an abstract entity endowed with temporal properties. For these reasons, Irmak (2010) definies software as an abstract artifact.