Time Reports provide the following report types:
Timesheet - provides the most extensive means to analyze users' workload. It has classical sheet view by day. Also with numerous report Options it is possible to get few variants of the report.
Pivot by Users - displays a summary of worked hours for project for certain period, where columns are project users (resources) and rows are project issues (tasks).
Pivot by Status - displays time worked on issues in each issue status. This report spreads worked hours across statuses issue had starting from work started time. It may be changed not to spread worked hours, but use only work started time, by enabling Use Work Started option in add-on configuration.
Time Tracking - displays Estimated Time vs Actual Time Spent per issue (no worklog).
Pie Chart - displays a summary of worked hours for project for certain period in Pie Chart.
All report types have various configurable parameters.
Just go to Administration - Plugins - Install in your Jira, search for 'timereports', see 'Time Reports' and click install.
When installed Time Reports Add-On adds Time Reports dashboard item and project report with the same name.
Report is accessible via menu Projects - some project - Reports tab - Other category, unless you have Jira Service Desk. See also Jira Documentation for more information.
Dashboard item can be added to Jira Dashboard, see Jira Documentation for more information.
Time Reports underlying data (worklog) can also be exported to Excel on the report page.