what programming languages should be known by a programmer in order to create an app like amazon or ali express?

Question

I am curious

Answer 1

It is very complicated because there are a lot of stuff involved.

But basic programming languages:
- HTML
- PHP
- JavaScript
- jQuery
- SQL

Answer 2

They are developed with https://www.sololearn.com/Course/fullstack/?ref=app

Answer 3

For Amazon: JavaScript, Java, C++ and Perl is used
https://en.m.wikipedia.org/wiki/Programming_languages_used_in_most_popular_websites