A swimlane diagram is a tool that you can use to get a detailed view of a process in your business.
It's used when you need a deeper understanding of a process than a process narrative can provide.
It's useful when trying to get more efficient with your process or as training documentation for new employees.
Oftentimes, just by creating a swimlane diagram of a process, you'll see 2-3 things you can do immediately to make the process better.
This podcast references a diagram that can be seen on the Optimize For Outcomes website at https://www.optimizeforoutcomes.com/wp-content/uploads/2021/08/Restaurant-Seating-scaled.jpeg