The "SPL" in Splunk refers to "search processing language", which is used by Splunk to query data that has been indexed.  An "index" is like an enormous catalog of all the information that Splunk knows about—it's where we keep track of everything so we can find it quickly when we need it!

To get statistics for an index, we use commands called "stats" and "summary."  These let us see how much data there is in the index, what kind of data it is (like whether it's words or numbers), and other helpful info.  This helps make sure the indexes are healthy and strong and have all the stuff they need to be useful.
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence