Docs are awesome but it's always better to try it on your own
You are literally just one click away!
Default report for all worklogs created within last 30 days.
Daily report for last 30 days set as a smart period.
Example of a report with data pivoted based on users and worklogs, not issues. That may be helpful if you have long lasting issues with multiply worklogs entries.
Sampe report based on issues from multiple projects
Saved Pivot reports can be customized in many ways. This is example of a report with Pivot tabs only.
Learn more about tabs in Pivot Report
Pivot Report allows you to visualize the data using several chart types.
Demo of custom hierarchy built with issue links set in the Pivot Report settings.
More information about custom hierarchy can be found here.
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
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.
Sample Pivot Report for the Backlog created directly from the Agile Boards.
Learn more about ways to create Pivot reports