Mork is a computer file format used by several

email client An email client, email reader or, more formally, message user agent (MUA) or mail user agent is a computer program used to access and manage a user's email. A web application which provides message management, composition, and reception functio ...

s and

web browser A web browser, often shortened to browser, is an application for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's scr ...

s produced by

Netscape Netscape Communications Corporation (originally Mosaic Communications Corporation) was an American independent computer services company with headquarters in Mountain View, California, and then Dulles, Virginia. Its Netscape web browser was o ...

and

Mozilla Foundation The Mozilla Foundation is an American non-profit organization that exists to support and collectively lead the Open-source software, open source Mozilla project. Founded in July 2003, the organization sets the policies that govern development, ...

. It was developed by David McCusker with the aim of creating a minimal

database In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...

replacement that would be reliable, flexible, and efficient, and use a file format close to

plain text In computing, plain text is a loose term for data (e.g. file contents) that represent only characters of readable material but not its graphical representation nor other objects ( floating-point numbers, images, etc.). It may also include a lim ...

. The format was named after the character Mork from the TV show ''

Mork & Mindy ''Mork & Mindy'' is an American television sitcom that aired on ABC from September 14, 1978, to May 27, 1982. A spin-off after a highly successful episode of ''Happy Days'', " My Favorite Orkan", it starred Robin Williams as Mork, an extrater ...

''.

Usage

The Mork format was used in most Mozilla-based projects, including the Mozilla browser suite,

SeaMonkey SeaMonkey is a free and open-source Internet suite. It is the continuation of the former Mozilla Application Suite, based on the same source code, which itself grew out of Netscape Communicator and formed the base of Netscape 6 and Netscape ...

Firefox Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements curr ...

, and Thunderbird. In Firefox, it was used for browsing history data and form history data. In Thunderbird, it is still used for many things, such as address book data (.mab files) and the mail folder summaries (.msf files).

Criticisms

Mork has many suboptimal properties. For example, despite the aim of efficiency, storing

Unicode Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Char ...

text takes three or six

bytes The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...

per character. The file format has been severely criticized by

Jamie Zawinski Jamie Werner Zawinski (born November 3, 1968), commonly known as jwz, is an American computer programmer, blogger, and impresario. He is best known for his role in the creation of Netscape Navigator, Netscape Mail, Lucid Emacs, Mozilla.org, an ...

, a former

engineer. He has criticized the apparent "textual" format on the grounds that it is "not human-readable", complaining that the impossibility of writing a correct

parser Parsing, syntax analysis, or syntactic analysis is a process of analyzing a string of symbols, either in natural language, computer languages or data structures, conforming to the rules of a formal grammar by breaking it into parts. The term '' ...

for the format, and referred to it as "...the single most braindamaged icfile format that I have ever seen in my nineteen year career". In response, McCusker stated that the problems with Mork resulted from "conflicting requirements" and that he merely fixed scalability issues in bad code he "inherited". ''

The Register ''The Register'' (often also called El Reg) is a British Technology journalism, technology news website co-founded in 1994 by Mike Magee (journalist), Mike Magee and John Lettice. The online newspaper's Nameplate_(publishing), masthead Logo, s ...

'' lambasted the Mork database with their article "Why has Thunderbird turned into a turkey?"

Obsolescence

The replacement system, used for storing all user configuration data, is called MozStorage. MozStorage is based on the

SQLite SQLite ( "S-Q-L-ite", "sequel-ite") is a free and open-source relational database engine written in the C programming language. It is not a standalone app; rather, it is a library that software developers embed in their apps. As such, it ...

database. Beginning with Firefox 3.0, Firefox uses it for its history, form history and bookmark data. The storage engine was also included in Firefox 2.0, but only for use with extensions. Mork was completely removed from Firefox in 2011. Plans existed for Mork to be replaced with MozStorage in Thunderbird 3.0., but as of 2025 still used the Mork file format. As of 2012, SeaMonkey used Mork for at least its POP and IMAP mail folders indexes.

References

External links

McCusker's description of the syntax

Grammar as mentioned in the above syntax description
*
Mozilla Wiki Mork page
(including links to tools for reading Mork documents) {{DEFAULTSORT:Mork (File Format) Computer file formats Mozilla

Usage

Criticisms

Obsolescence

See also

References

External links