Ok, so I have this slideshow from HTML Kickstart. (see it at http://www.99lime.com/elements/)
It goes through a list of images by adding/ removing the class “current”.
I’m trying to make the page, so that whenever the image changes, the comments and tags on the page also changes, without refreshing the page.
I’m not sure how to approach this using either GET/POST methods in my app.py. Or would it be javascript/jQuery. Thanks.

Let us imagine that user A and user B enter the page at the same time and see the 2 comments that others wrote before them and that both user1 and user2 write a comment each and that neither of them refreshes the page but instead keep staring at the slideshow. There will be 4 comments in the database, but if AJAX is not used for loading the new comments and tags, A and B will be seeing 3 comments, namely the previous 2 comments and their own new comment.
If this is acceptable, you do not need to use AJAX.
If this is not acceptable, you need to use AJAX.
If you decide not to use AJAX, just pre-load the comments and other things show and hide them according to which slide you are on. If you alter the class of an element that contains the comments and make it ‘onslide1’ when you are showing the first slide ‘onslide2’ when you are showing the second and so on, you can use CSS rules to show the ones you want as follows:
An even simpler solution? Things may be even easier if you can incorporate this information in your slides. This would mean that instead of plain images you have some simple HTML that shows both an image and the comments and everything else you want to associate with the slide.
To load comments and other stuff using Ajax, you will need to work both on the server side and on the client-side (ensure you perform the Ajax call as the slide changes or before that (possibly changing the slide exactly at the moment you receive your data)). If you do go this route and you need further help, its probably best if you ask a separate question specifying your decisions and what you want to achieve. (This was more of a question asking for advice on the general strategy.)