On the Photos page, you can see all the pictures that were shared by members in their profiles.
In the left top, where it says 'Photos Home' in blue, you can change the view, for example to see the top rated photos, all featured photos, photo albums, etc. You can also use the 'Rater' to easily scroll through photos and rate them with 1 - 5 stars.
You can share your own pics. Start by clicking on the blue + in the right top, and then choosing an existing photo album or create a new one. (you can only see the + when you are logged in).
You can upload photos, but also share them from your Instagram or other social media. Then the views are added to your account. To do this, you change the 'mass uploader' option into 'embed', and then simply copy and paste the link to your photo.
All the photos that you share, will appear in your profile, and also on this photos page, as well as on the home page. They can also be found under the categories that you have set.