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 ## Description
 
+The API is very important part of ReCodEx project. It provides common interface for usage in different user frontends such as default web application, mobile applications, commandline tools and possibly others. The communication goes as HTTP(S) requests in predefined format, nowadays mostly known as [REST](https://en.wikipedia.org/wiki/Representational_state_transfer) format. Results from the API are in plain text in JSON format to be easily parsed in various languages (notably JavaScript).
+
+This component must be publicly visible in the internet, so it's important to care about security and follow our recommendations. We have really focused on security aspect of the project, so proper roles with permission separation are introduced and maintained. Also some additional checks are made directly in the code, so user can't access informations which are out of his authorization.
+
 ## Architecture
 
 ## Installation