A text file can contain any stream of characters, including possible control characters, and is encoded in one of various character encoding schemes. Other file formats, however, are designed for storage of several different types of data: the Ogg format can act as a container for different types of multimedia including any combination of audio and video, with or without text (such as subtitles), and metadata. Some file formats are designed for very particular types of data: PNG files, for example, store bitmapped images using lossless data compression. File formats may be either proprietary or free and may be either unpublished or open. It specifies how bits are used to encode information in a digital storage medium. A file format is a standard way that information is encoded for storage in a computer file.
