In the past, manufacturers have developed many different display systems in a competitive, non-collaborative basis (with a few exceptions, as the VESA consortium), creating many proprietary, non-standard different instances of display hardware. Often, as with early personal and home computers, a given machine employed its unique display subsystem, with its also unique color palette. Also, software developers had made use of the color abilities of distinct display systems in many different ways. The result is that there is no single common standard nomenclature or classification taxonomy which can encompass every computer colour palette.