The Daily Active Addresses (DAA) graph shows the number of unique network addresses involved in transactions on a certain date. Simply put, DAA indicates the daily level of interaction with a certain token.
This is a 1-year DAA graph for ZIL (Zilliqa). As you can see, there’s been a massive spike in daily active addresses at the beginning of May 2018, a significant spike in DAA may indicate that the interest in a project is increasing.