Publisher 2013 allocates the space sounding your publication as a scratch area into which it places pictures that you can insert into your publication pages. If you insert multiple pictures at the same time when using either the “Insert Picture” dialog box or the “Insert Pictures” windows, Publisher will add the selected pictures into a column within the scratch area to the right of your publication page.
You can click and drag the pictures from the scratch area into your publication pages. Likewise, you can click and drag a picture off of a publication page and drop it into the scratch area. You can also swap pictures that appear within the scratch area within pictures in the publication pages. To do this, click the icon of the mountain shown within the middle of the picture in the scratch area and drag it onto a picture within a publication page. When the border of the picture in the page turns pink, you can release the mouse button to swap the image from the scratch area with the existing picture.
You can also set a picture as the background of a publication page. To do this, right-click on a picture within the scratch area of publication page. Then roll over the “Apply to Background” command in the pop-up menu that appears. Then from the side menu that appears, click either the “Fill” command to fill the entire background of the page with the selected image or click the “Tile” command to tile the selected image over the page.
Watch this video for more examples of using the scratch area in Microsoft Publisher 2013: