But what it can do is at http://www.irfanview.com/ which I won't duplicate here.
Why some will download and use such is they don't have a viewer or convertor for some graphic format. There is also some finer optimizing for some of the graphic formats.
Not everyone needs it.
I just downloaded the latest version of Irfanview. After three tutorials, I still cannot figure out what it will do that my other graphics and photo editing programs will not do. I realize that a lot of people use it. Am I missing something?
PowerPoint Slide Viewer