Docs are awesome but it's always better to try it on your own
You are literally just one click away!
Custom Slices demo
Pivot Report is highly configurable. This demo report has custom slices: display value is set to Remaining time instead of issue counts, and all slices are based of custom JQL.
Custom slices tutorial
Worklogs report based on a filter
Jira time tracking is kind of in place, but not really an easy thing to use. But luckily for you Pivot Report can help with better display of spent time.
Another example of the Pivot Report power: Capacity tab. It helps you get something meaningful from the due dates in issues. Original Estimates per assignee are mapped to periods like a month, two weeks, etc. with an option to split period by days.
Default report for last 30 days
Default report for all worklogs created within last 30 days.
Split by day for the last month
Daily report for last month set as a smart period.
Last week report, worklogs as rows
Example of a report view where data is pivoted based on users and worklogs, not issues. That may helpful if you have few long lasting issues with multiply worklogs entries.