A Platform is a group of technologies that are used as a base upon which other applications, processes or technologies are developed.
In personal computing, a platform is the basic Hardware (H/W) (computer) and Software (SW) (operating system) on which software applications can be run. This environment constitutes the basic foundation upon which any application or software is supported and/or developed.
Computers use specific Central Processing Units (CPUs) that are designed to run specific machine language code. In order for the computer to run software applications, the applications must be in that CPU’s binary-coded machine language.
Thus, historically, application programs written for one platform would not work on a different platform.