YAML is a simple markup language that uses the syntax that can be easily read by non-programmers.
Important links:
The YAML files should have a .yaml extension source.
Characters with special meaning in YAML¶
The following characters have special meaning in YAML: {, }, [, ], &, *, #, ?, |, -, <, >, =, !, %, @, :, ` and ,. In strings, these characters should be quoted. They have to be avoided in keys.