Understanding how applications talk to each-other - REST APIs etc

Hello Friends,

I just wonder if I could get your views on learning APIs. In particular I want to understand how applications talk to each-other, for example - Google APIs, FreshService/Desk API. I want to understand how data can be pushed from different apps and then even get to understand how Wappler handles these APIs.

Id like to also understand the theory behind JSON, which I gather is the format is which data is passed over via APIs using GETs and POSTs.

So, I’m looking at this course - https://www.udemy.com/course/nodejs-the-complete-guide/ and just wondered from what you’ve read from the above does that seem the right way to go? There is a lot in this sure I’d welcome your thoughts. In terms of my knowledge - I’m a complete newbie to the world of APIs - but have a very basic understanding.

Thanks
M