It also can switch easily photos into fullscreen view (I use the center button of the mouse for that) and then you can browse photos using mouse wheel or l/r arrow keys.
No need to import photos into a library, we can use directly our photo folders which is HUGE for me.
It supports many languages, and above all it's FREE (for personal use). I am an amateur photographer used to ACDSee but the Mac version is horrible so I decided to look for something similar for Mac and this is the best software I found for that. I am a windows user but it's for my gf who uses a Mac. TokyoQuaSaR's Experience I have used this tool for only 2 hours.