To work with APIs you must have a basic understanding of APIs, REST, SOAP, OAuth, Swagger, and WebSocket. You must also be able to read computer code. This guide is not a primer for these topics. The procedures and processes assume that you understand these concepts. There are many different sources of information about these topics. Here are a few of the topics you must know:
APIs
OAuth 2.0
REST
SOAP
Swagger
WebSocket