This is an organized system for people with lots of images.
Here's how it works for me.
My groups are sports, weddings and portraits.
Click on sports. inside this GROUP are two groups; football and horseshows.
click on horse shows. Inside this GROUP are 3 GROUPS; fairfied horse show, manchester horse show and Ridge horse show.
Click on the ridge horse show and there are GALLERIES.... beginner jumper, adult jumper and open jumper.
look at the 500 photos. See pictures of you riding? put them in a COLLECTION and send the url to Dad's office telling him these are the ones he needs to buy for you.
A Group is like a folder on your computer. You can put a computer folder inside another folder... THE ADVANTAGE OF GROUPS IS you can have different rules for each group. So my price list for horse shows are not the same as portraits or football.. ..... nor is my access. I can make the football open to the public and close portraits to only those with a password.
A GALLERY is the place that holds the individual image files. (such as "beginning jumpers" or "open jumpers". All you images should be uploaded to Galleries. Then you put the galleries into groups (even if it's a group titled miscellanous shots or my favorites)..
A COLLECTION is mainly for the customer to sort out there images from the Gallery.