Every client is important to you, and the last thing you want is to make them feel like they're just another face in the crowd. Tags are like a keyword you place on the contact record that denotes specific attributes about a contact.
For example, if you just entered a new contact into Keap, you can tag them as a new prospect. That way you keep your contacts organized in a way that makes it easier for you to engage, communicate, and offer your products and services. This ensures that your clients get the communications that are most impactful to them.