User blog comment:Zmario/Share Your Knowledge/@comment-26955746-20150825014930

The MultipleUpload tool can be used to upload up to 10 images at once for regular users, and 20 for admins. The "What links here" feature found under "My Tools" in the toolbar is also useful as it allows you to see what pages links to articles/redirects/files etc. can be found on. This is especially useful for admins when deleting pages etc. for cleanup purposes. Also remember to add your favourite and most used tools to the toolbar using the "Customize" button.

Edit: If you ever want to replace a file with an improved version, rather than uploading a completely separate image and deleting the old one, use the "replace" option from the dropdown menu on its file page. Note that the replacement image must have the same file format as the image its replacing. i.e. you can't replace a .jpg with a .png for example.