A YAML file is a document created in the YAML (YAML Ain't Markup Language) format, a human-readable data format used for data serialization. It is used for reading and writing data independent of a specific programming language. YAML files are often configuration files, used to define the settings of a program or application.
YAML file open in Atom
Because the YAML format is not language-specific, YAML files can be included and referenced within programs written in any language that supports YAML libraries, such as C/C++, Ruby, Python, Java, Perl, C#, and PHP. The YAML acronym originally stood for Yet Another Markup Language, but as the YAML format evolved, the acronym adopted its current, recursive meaning.
NOTE: While the programmer community recommends saving YAML files with the YAML extension, you might also encounter YAML files saved using the .YML extension.
You can open a YAML file in any text editor, such as Notepad (Windows) or TextEdit (Mac). However, if you intend to edit a YAML file, you should open it using a source code editor, such as NotePad++ or Atom. These applications provide helpful source code editing tools and highlight YAML syntax correctly.