Tags can be used to help you sort through your leads and customers. It's a great way for you to better manager a long list of clients and identify special cases (e.g. a hot lead, a VIP client, etc)
Examples of how to use tags:
Tag to identify Hot or Cold leads.
Tag customers that are VIP or Veterans etc.
Tag leads in a specific stage (e.g. Quoted) to identify where they are in the sales process.
Use tags to quickly filter through your customer list or lead list.
Apply automation based upon tags
Here's a quick video on how to:
Manage your tags.
Tag a customer and a lead.
Create filters based on tags.