How Do I Do That in Photoshop?

See More Than One Image at a Time?

When you open multiple images, they open kind of like panels do—you see the active image in front, and then little tabs (in the top of the image window) for the other open images behind it (if you have this tabbed viewing set in your Preferences). If you want to see all the images onscreen at the same time, go under the Window menu, under Arrange. At the top of the menu are a bunch of choices for how you can display them: show them all in thin vertical tiles or horizontal tiles, or display two, three, four, or ...