Are there standards, rules, common syntax for writing echo web service?

Question

Web development

Friends, I'm sorry to distract you with such nonsense, at the university they gave me the task to implement a simple echo web service. I roughly understood what it is, but it is very difficult to find specific information - Google gives out a huge amount of information about creating web services in php. Can you please tell me if there are any standards for echo web services? Can generally accepted solutions, a certain syntax for naming fields? Where can you even read about them?

Answer 1

echo - the server gives back what it receives. Because he and "echo." In the context of a web service, information about the request is usually given as a response.

Answer 2

To be honest, this is the first time I've heard of this. I think it should mean something like "hello world" for web services, i.e. you send some test data and it simply returns them, thus showing that it works.