You can actually set your properties and values to be whatever you want them to be. This would all depend on how you have things set up and for your own organizational purposes. In addition to the Help Center articles that @k.mcevoy included, I would suggest taking a look at the following resources that can further help you understand how to utilize profile properties with conditional splits:
The ROI of your reply? One helpful answer can support dozens of teams, build your credibility, sharpen your own expertise over time, foster connectivity, and create good karma – because what goes around comes around. The community is what YOU make it.