When you create or edit a Folio, you will see that there is a Tag List option near the top of the page. For Entities and Contacts, the tags List option is near the bottom. To create a tag, start to type a key name - it will bring up the tags that are already there. If it is not there you can create a new tag by simply typing in the term and clicking on enter.
Tags are really useful means of grouping data in a flexible way and they can be used to help find information - either by accessing it through our Tag Clouds or as a filter in our list screens or as a filter in our reports.