hocon is an configurable data for environment settings like dev, test, stage and production environment.

HOCON is an super set of JSON with features - includes, substitutions comments

Let’s see the difference between the two file formats.

Hocon   yaml  
Configuration language for different test,production environments markup language syntax easily understand by Human readability
Supports includes and Substitutions No support
Comments are supported Comments are supported
Support DRY and inheritence principles extended using tags