YAML is a human-friendly format for structured data, that is both easy to write for humans and still parsable by computers.

=== PyYAML parser ===

[[http://pyyaml.org/|PyYAML]] is the most-used and go-to YAML package, which tries to be as compliant as possible with the YAML specs. It is, at its core, C-based. It can both read and write YAML. You can read the [[https://pyyaml.org/wiki/PyYAMLDocumentation|official documentation]], or try the condensed/simplified version of these docs, with usable example code on this [[https://python.land/data-processing/python-yaml|Python YAML tutorial]].

When using this package, be careful which function you use. The `load()` function is very powerful and allows arbitrary code execution, while the `safe_load()` function is enough for most use cases. It only allows a subset of the load function, making it a much safer choice. For more details, see also the [[https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load(input)-Deprecation|load deprecation notice]].

=== YAML examples and usage in notable Python apps ===

YAML is a feature-rich language. Some packages that heavily depend on YAML are:

 * tmuxp - http://tmuxp.readthedocs.org/en/latest/examples.html
 * ansible - http://www.ansibleworks.com/docs/YAMLSyntax.html and http://www.ansibleworks.com/docs/playbooks.html#id9
 * appengine - https://developers.google.com/appengine/docs/python/config/appconfig and https://github.com/rietveld-codereview/rietveld/blob/master/app.yaml
 * salt - http://docs.saltstack.com/topics/tutorials/starting_states.html#default-data-yaml