Apart from Picasa's indisputable first position among image viewers, there's a very interesting competition in the Top Downloads list for this category on Softonic. Two of the most powerful candidates are FastStone Image Viewer and XnView, two popular image viewers that share many features but also have certain differences. Let's analyse both of them in depth.

When launching both programs, the first noticeable difference is their interface. Whilst XnView looks very much like Windows Explorer, with a tree-like structure on the left and the selected folder's contents on the right, FastStone Image Viewer uses a neatly designed interface that you can customize with skins. Both programs use thumbnails to display photos and ALT text windows to show detailed information about each picture.

Anyone who works with images on a regular basis will be familiar with the default image viewer of Windows, and also with its very limited scope for doing anything meaningful. There is a healthy selection of alternatives but FastStone Image Viewer has come to our attention as one that deserves to be singled out not only because it is free but also because it brings to the table a strong combination of speed, usability and versatility.

While the viewing functionality is a no-brainer, FastStone comes with a range of methods with which to browse pics. First off, there is the standard file browser that displays thumbnails of your images with a preview window for the file that is currently selected. There is also an option to check out individual pictures at their original size in the "Windowed View", which is along the same lines as the default image viewer in Windows. Finally you can see images in full-screen, switching between files using the keyboard, the middle mouse button or the slide-in toolbar at the bottom of the screen.

While Windows already features a basic photo viewer, it's good to have a more complete alternative to enjoy your pictures like FastStone Image Viewer. With this application you can not only review your photo collection in several ways, but also perform some basic editing tasks, convert files from one format to another and rename them as well.