It is important to know how to get basic information about your cluster. Which node is the elected master? How many shards do I have on each node? What state is my cluster in? How many documents do I have in each index? All of these quests and a whole lot more are answerable by the Compact and Aligned Text (CAT) APIs. In this video we cover the common parameters for the CAT APIs, how to use them on the cammand line and Kibana's console tool, and how to use the various parameters to find and format the exact data we want to see.