Exporting and importing web parts allows you to reuse the effort spent in setting up a web part as all the web part settings are automatically retained. This can be a useful way of reusing complicated reports.
Export a Web Part
Click the Page | Edit Page.
Click the down arrow on the web part you want to save and click Export.
Pick a suitable location to save to, and click Save.
Import a Web Part
Click the Page | Edit Page.
Click Add a Web Part in any section.
In the new window that appears, click the down arrow next to Upload a Web Part, then click Choose File.
Once you've picked your file, click Upload.
Now you'll find your uploaded web part in the Imported Web Parts category, ready to be added when you click Add a Web Part in the Edit Page screen.