I have a ton of photos on an external hard drive that I backed up from my Windows PC. This is my first mac. On Windows, I could simply connect the external HDD and open the folders and view each folder by thumbnail. I can view the contents of the folder by small icon, large icon, thumnail, etc. When I connect my external HDD to my iMac, I can't tell what I am looking at until I double click the icon. And the default photo app seems to be Preview which is hard to manipulate (making photos full screen at the click of a button). Does OS X have similar features to Windows where I can view the folders by thumbnail? Because the easiest way I found was to upload everything onto iPhoto. But the point was that I wanted to view what each photo was so I can upload only a few photos into iPhoto.