The general purpose of a colour space is to determine the range of colours available within a specific workflow and may be determined by a user or programmatically.
The Adobe RGB (1998) colour space aims to ensure the optimal range of colours available within the RGB colour model are accurately reproduced when output to digital displays or printers.
In a digital environment, the aim is to ensure that a selected range of colours appears consistent throughout a workflow and that the desired range of colours is successfully reproduced at the end of the process.