Empathy map is a synthesis framework to externalize & communicate your understanding & empathy for a specific user type.
This is a great exercise to do on a whiteboard with sticky notes right after performing user research, like observations and interviews.
Empathy maps can be used as a way to extract meaningful insights. For example, it can pull apart how users are saying something different from what they actually do. These maps can also serve as a foundation for building out more comprehensive personas and journey maps.