A developer is anyone who "developers" any application, software or website, through the use of programming languages.
Some of the lenguages known are:
HTML, Javascript, SQL, PHP, ASP, XML among others.
The previous languages refer to languages used in website development.
Code C, Code C++, Java, Assembly, among others.
The previous languages refer to languages used in software development.
A developer in most cases, is recognized by the use of different programming languages but in some cases could get to use block software.