We’ve already seen the use of a custom attribute on a virtual machine. At first glance tags and custom attributes seem to be similar, but there are good reasons to use one over the other.
Tags are better if we wish to categorise, sort or filter an object based on its tag. We could for example quickly search for all items tagged with a particular value. A tag must exist within a category before it can be used however, and so we have to consider the manageability of tag categories that contain many hundreds of different tags.
Custom Attributes are better if we just wish to assign a generic text string to an object, but don’t need to sort or categorise objects by the attribute name or string.