The "Back" button MIGHT just re-display the page that you previously viewed without re-accessing the web site server, showing what has already been downloaded into your computer's temporary internet directory (Cache). Thus the photos MIGHT not change. If there is a page selector list on the pages and you click on Page 2 and then Page 1, that will cause the browser to re-access the server and it may then send you a "new" arrangement of photos, (assumming the server is actually randomizing the photos on each page from the total list of photos).
The "Forward" button will do likewise. If you start on Page 1 and then go to Page 2, the back button MIGHT just show the original Page 1 you saw before and then the "Forward" button MIGHT take you to the original Page 2 you saw. Of course, the randomizer function may have randomly selected the same photos in the same order for the original Page 2 as the original Page 1 so it is conceivable that you will only see the page number change! (not very likely, but possible).
You MIGHT be able to alternately click the "Back" and "Forward" buttons and see the same two pages repeatedly.
I capitalized "MIGHT" up there because there are settings that you can make to your browser that will cause it to always re-access the web site when using the BACK and FORWARD buttons, regardless of what is in the cache. So, if your particular setup has the brower reloading each page, then you may see new photos each time, no matter what.
The "Forward" button will do likewise. If you start on Page 1 and then go to Page 2, the back button MIGHT just show the original Page 1 you saw before and then the "Forward" button MIGHT take you to the original Page 2 you saw. Of course, the randomizer function may have randomly selected the same photos in the same order for the original Page 2 as the original Page 1 so it is conceivable that you will only see the page number change! (not very likely, but possible).
You MIGHT be able to alternately click the "Back" and "Forward" buttons and see the same two pages repeatedly.
I capitalized "MIGHT" up there because there are settings that you can make to your browser that will cause it to always re-access the web site when using the BACK and FORWARD buttons, regardless of what is in the cache. So, if your particular setup has the brower reloading each page, then you may see new photos each time, no matter what.