IrfanView is a very fast, small, compact and innovative FREEWARE (for non-commercial use) graphic viewer for Windows 9x/ME/NT/2000/XP/2003/Vista.
It is trying to be simple for beginners and powerful for professionals. IrfanView is trying to create new and/or interesting features in its own way, unlike some other graphic viewers, whose whole "creativity" is based on feature cloning, stealing of ideas and whole dialogs from ACDSee and/or IrfanView! (for example: XnView has been stealing/cloning features and whole dialogs from IrfanView, for 8+ years).
IrfanView was the first Windows graphic viewer WORLDWIDE with Multiple (animated) GIF support.
One of the first graphic viewers WORLDWIDE with Multipage TIF support.
The first graphic viewer WORLDWIDE with Multiple ICO support.