When creating a query, I often see call and call legs in the Talk dataset's metrics and attributes. What is the difference between calls and call legs?
Call metrics such as Calls, Completed calls and Inbound calls count the entirety of the call while call legs count a specific segment/event in the call. For more information about call legs, see the article: Understanding call legs.
Call legs are useful to look at specific events in the call cycle such as missed calls by agents, accepted and declined calls by an agent, and calls that went to voicemail.
For more information about call reports in Explore, see the article: Reporting on calls with Explore (Talk Professional and Enterprise).