Despite the popularity of SOA and Microservice Architectures, some technological and implementation details are often missunderstood or incorrect interpreted. In this article, we will review seven facts about Web Services that can help developers to better understand the concepts and also to better prepare for interview questions if needed.
You may also The HTTP Series (Part 1): Overview of the Basic Concepts.
HTTP Is Absolutely Required for RESTful Services
HTTP is not formally required for RESTful web services, but if HTTP methods are used, their formal meaning should be strictly followed so that without additional effort the clients can understand the API (e.g. do not use POST to update data, it is supposed to only create resources and is not idempotent by nature).