I’m a pretty fairly new coder. I used the different languages for a few reasons. I used python to build the bases of the app. I then was using shell script to tie it with paypal to have a payment system set up. Then Finally I was using Javascript to create the features of the website. I do not have them calling each other or anything I do not have the knowledge yet to do that. The reasoning for this code is I am running a business that sells products and I wanted to create an app in which people could go on and buy the products without my having to do much work.