Confluence 5.6 has reached end of life
Check out the [latest version] of the documentation
Type an exclamation mark '!' and start typing the image name to see the suggested images to insert onto the page. Press the arrow keys to select the item you want. Example:
Alternatively, use wiki markup entirely. Type the wiki markup for the image insertion, including the exclamation marks, the space and/or page name (if different from the current page) and the image name, as well as any other allowed parameters. As soon as you type the closing exclamation mark, Confluence will convert the image to rich text format and add it to the page. This means that you can skip the image browser.
!NoMatterWhat.png|align=right!