Sitefinity CMS Libraries module lets you organize your images, documents and videos in a hierarchical structure.
Libraries are at the top (root) level, and folders are the branches and sub-branches of a library.
A library configuration describes its security, location, and URLs. It can also be a container for media content with specific extensions, such as images, documents and videos.
A folder is just a container for media content in its scope.
This article provides information of how use
LibrariesManager to manage folders using the Folders API.