Tags are essentially labels that you can assign to any domain, hosting plan, owner or provider. Each tag can have a name, a color and some notes associated with it and each tag can be assigned to any entry - except another tag. One entry can only have one tag associated with it. Tags provide the possibility of a secondary classification system that you define in any way you want. For example you can create a tag called Important for the most important domains, hosting plans or even customers. Or you could create a tag to easily mark domains that should not be renewed when they expire. There are virtually endless possibilities.