Documents contain one or more files. Documents can be either owned or referenced, and the files within a document can be either versioned or nonversioned.
A folder that resides in a data category is called a simulation folder. To help you keep your data organized, you can create simulation folders that store specific documents. For example, you could create a Materials folder inside the specifications category to hold all of the files that define your material behavior. You can create a simulation folder inside a data category, and you can create a simulation folder inside an existing simulation folder (subfolders).
You can remove obsolete and temporary files from a document by archiving and purging the document. Archiving allows you to save the files in a local directory; purging removes the files from the document.