MHTML files use a .mhtml or .mht filename extension. ISO image files bear the ".iso" filename extension. This forced costly filename encoding guessing with each file access. The name refers to its executable filename. The most common filename extension for files containing HTML is .html. The common filename extension of WordPerfect document files is codice 1. A file is stored into the system by computing the hash of its filename. When a filename is moved to an existing filename, the existing file is deleted. OneNote files have a codice 1 filename extension. File systems have not always provided the same character set for composing a filename. File systems also have a limit on the length of an individual filename. These files respectively have codice 2 and codice 3 filename extensions. The JPEG/JFIF filename extension is JPG or JPEG. Read files from "somedir" into an RDD of (filename, content) pairs. The backups are in a proprietary format which saves using a .tib filename format.