Internet Movie Database

The Internet Movie Database (IMDb) is an online database of information related to films, television programs, and video games, including actors, production crew personnel and fictional characters featured in these three visual entertainment media.

It is one of the most popular online entertainment destinations, with over 100 million unique users each month and a solid and rapidly growing mobile presence. IMDb was launched on October 17, 1990, and in 1998 was acquired by Amazon.com. As of January 7, 2013, IMDb had 2,393,341 titles and 5,010,177 personalities in its database. As of January 17 2013 IMDb had 40,000,000 Registered Users

History before website
IMDb originated with a Usenet posting by British film fan and professional computer programmer Col Needham entitled "Those Eyes", about actresses with beautiful eyes. Others with similar interests soon responded with additions or different lists of their own. Needham subsequently started a (male) "Actors List", while Dave Knight began a "Directors List", and Andy Krieg took over "THE LIST", which would later be renamed the "Actress List". Both lists had been restricted to people who were alive and working, but soon retired people were added, so Needham started what was then (but did not remain) a separate "Dead Actors/Actresses List". The goal of the participants now was to make the lists as inclusive as possible. By late 1990, the lists included almost 10,000 movies and television series correlated with actors and actresses appearing therein.

On October 17, 1990, Needham developed and posted a collection of Unix shell scripts which could be used to search the four lists, and thus the database that would become the IMDb was born. At the time, it was known as the "rec.arts.movies movie database", but by 1993 had been moved out of the Usenet group as an independent website underwritten and controlled by Needham and personal followers. Other website users were invited to contribute data which they may have collected and verified, on a volunteer basis, which greatly increased the amount and types of data to be stored. Entire new sections were added. As the site grew hugely, full production crews, uncredited performers and other demographic data were added. Needham's group allowed some advertising to support ongoing operations of the site, including the hiring of full-time paid data managers. All the primary staff came (and still come) from the burgeoning computer industry and/or training schools and did not have extensive expertise in the visual media. In 1998, unable to secure sufficient funding from limited advertising, contributions and unable to raise support from the visual media industries or academia, Needham sold the IMDb to Amazon.com, on condition that its operation would remain in the hands of Needham and his small cadre of managers, who soon were able to move into full-time paid staff positions.

On the web
The database had been expanded to include additional categories of filmmakers and other demographic material, as well as trivia, biographies, and plot summaries; the movie ratings had been properly integrated with the list data; and a centralized email interface for querying the database had been created by Alan Jay. Later in the year it moved onto the World Wide Web (a network in its infancy at that time) under the name of Cardiff Internet Movie Database. The database resided on the servers of the computer science department of Cardiff University in the UK. Rob Hartill was the original web interface author. In 1994 the email interface was revised to accept the submission of all information, meaning that people no longer had to email the specific list maintainer with their updates. However, the structure remained that information received on a single film was divided among multiple section managers, the sections being defined and determined by categories of film personnel and the individual filmographies contained therein. Over the next few years, the database was run on a network of mirrors across the world with donated bandwidth.

The website is Perl-based. As of May 2011, the site has been filtered in China for more than one year, although many users address it through proxy server or by VPN.

On October 17, 2010 IMDb launched original video (www.imdb.com/20) in celebration of its 20th anniversary.

As an independent company
In 1996 IMDb was incorporated in the United Kingdom, becoming the Internet Movie Database Ltd. Founder Col Needham became the primary owner as well as the identified figurehead. General revenue for site operations was generated through advertising, licensing and partnerships.

As Amazon.com subsidiary
In 1998, Jeff Bezos, founder, owner and CEO of Amazon.com, struck a deal with Col Needham and other principal shareholders to buy IMDb outright and attach it to Amazon as a subsidiary, private company. This gave IMDb the ability to pay the shareholders salaries for their work, while Amazon.com would be able to use the IMDb as an advertising resource for selling DVDs and videotapes.

IMDb continued to expand its functionality. On January 15, 2002 it added a subscription service known as IMDbPro, aimed at entertainment professionals. IMDbPro was announced and launched at the 2002 Sundance Film Festival. It provides a variety of services including film production and box office details, as well as a company directory.

As an additional incentive for users, as of 2003, users identified as one of "the top 100 contributors" of hard data received complimentary free access to IMDbPro for the following calendar year; for 2006 this was increased to the top 150 contributors, and for 2010 to the top 250. In 2008 IMDb launched their first official foreign language version with the German IMDb.de. Also in 2008, IMDb acquired two other companies, Withoutabox and Box Office Mojo.

In 2011 IMDb was sued by an unknown actress for more than US$1 million due to IMDb revealing her age (40). The actress claims that revealing her age could cause her to lose acting opportunities. A federal judge in Seattle dismissed the lawsuit, saying the actress had no grounds to proceed with an anonymous complaint. She re-filed and so revealed that the complainant is a Huong Hoang of Texas, who uses the stage name Junie Hoang.

Television episodes
On January 26, 2006 "Full Episode Support" came online, allowing the database to support separate cast and crew listings for each episode of every television series. This was described by Col Needham as "the largest change we've ever made to our data model", and increased the number of titles in the database from 485,000 to nearly 755,000.

Characters filmography
On October 2, 2007 the characters filmography feature was launched. The feature is similar to the existing title, name and company feature, except now a biography about each character and the actors who played him are available along with memorable quotes. All data in the characters filmography is submitted by regular users and is largely not verified by the IMDb staff, in contrast to most other data submitted to the site, which is verified and by the staff. This lack of oversight is deemed acceptable, however, because very little new data is sent in; the majority of submissions consist of existing data being connected together.

Instant viewing
On September 15, 2008 a feature was added that enables instant viewing of over 6,000 movies and television shows from CBS, Sony and a number of independent film makers, with direct links from their profiles. Due to licensing restrictions, this feature is only available to viewers in the United States.

User ratings of films
As one adjunct to data, the IMDb offers a rating scale that allows users to rate films on a scale of one to ten. The rating system is recognized as being severely flawed for several reasons.

Filters and weights
IMDb indicates that submitted ratings are filtered and weighted in various ways in order to produce a weighted mean that is displayed for each film, series, and so on. It states that filters are used to avoid ballot stuffing; the method is not described in detail to avoid attempts to circumvent it. In fact, it sometimes produces an extreme difference between the weighted average and the arithmetic mean. For example, Jonas Brothers: The 3D Concert Experience is considered to be the worst film with a weighted average of 1.3 as of March 2009, but has a rather ordinary arithmetic mean of 4.1.

Ranking (IMDb Top 250)
The IMDb Top 250 is intended to be a listing of the top 'rated' 250 films, based on ratings by the registered users of the website using the methods described. Only non-documentary theatrical releases running at least forty-five minutes with over 25,000 ratings are considered; all other products are ineligible. Also, the 'top 250' rating is based on only the ratings of "regular voters". The exact number of votes a registered user would have to make to be considered to be a user who votes regularly has been kept secret. IMDb has stated that to maintain the effectiveness of the top 250 list they "deliberately do not disclose the criteria used for a person to be counted as a regular voter". In addition to other weightings, the top 250 films are also based on a weighted rating formula referred to in actuarial science as a credibility formula. This label arises because a statistic is taken to be more credible the greater the number of individual pieces of information; in this case from eligible users who submit ratings. IMDb uses the following formula to calculate the weighted rating:


 * $$W = \frac{Rv + Cm}{v+m} $$

where:
 * $$W\ $$ = Weighted Rating
 * $$R\ $$ = average for the movie as a number from 0 to 10 (mean) = (Rating)
 * $$v\ $$ = number of votes for the movie = (votes)
 * $$m\ $$ = minimum votes required to be listed in the Top 250 (currently 25,000)
 * $$C\ $$ = the mean vote across the whole report (currently 7.1)

The $$W\ $$ in this formula is equivalent to a Bayesian posterior mean (See Bayesian statistics).

The IMDb also has a Bottom 100 feature which is assembled through a similar process although only 1500 votes must be received to qualify for the list.

The top 250 list comprises a wide range of films, including major releases, cult films, independent films, critically acclaimed films, silent films and non-English language films.

Message boards
One of the most used features of the Internet Movie Database is the message boards that coincide with every title (excepting, as of 2006, TV episodes ) and name entry, along with over 140 main boards. This section is one of the more recent features of IMDb, having its beginnings in 2001. In order to post on the message boards a user needs to "authenticate" their account via cell phone, credit card, or by having been a recent customer of the parent company Amazon.com.

Data provided by subjects
In 2006, IMDb introduced its "Résumé subscription service", where actors and crew can post their own résumé and upload photos of themselves for a yearly fee. The base annual charge for including a photo with an account was $39.95 until 2010, when it was increased to $54.95. IMDb résumé pages are kept on a sub-page of the regular entry about that person, with a regular entry automatically created for each résumé subscriber who does not already have one.

As of 2012, Resume Services is now included as part of an IMDbPro subscription, and is no longer offered as a separate subscription service.

Copyright, vandalism, and error issues
All volunteers who contribute content to the database technically retain copyright on their contributions but the compilation of the content becomes the exclusive property of IMDb with the full right to copy, modify, and sublicense it and they are verified before posting. Credit is not given on specific title or filmography pages to the contributor(s) who have provided information. Conversely, a credited text entry, such as a plot summary, may be "corrected" for content, grammar, sentence structure, perceived omission or error, by other contributors without having to add their names as co-authors. Due to the process of having the submitted data or text reviewed by a section manager, IMDb is different from database projects like Wikipedia, Discogs, or OpenStreetMap in that contributors cannot add, delete, or modify the data or text on impulse, and the manipulation of data is controlled by IMDb technology and salaried staff. Nevertheless, although it is generally assumed to be reliable, IMDb has been subject to deliberate additions of false information, as acknowledged by a spokesperson in 2012: "We make it easy for users and professionals to update much of our content, which is why we have an 'edit page.' The data that is submitted goes through a series of consistency checks before it goes live. Given the sheer volume of the information, occasional mistakes are inevitable, and, when reported, they are promptly fixed. We always welcome corrections."

The Java Movie Database (JMDB) is reportedly creating an IMDb_Error.log file that lists all the errors found while processing the IMDb plain text files. A Wiki alternative to IMDb is omdb (Open Media Database) whose content is also contributed by users but licensed under CC-by and the GFDL. Since 2007, IMDb has been experimenting with wiki-programmed sections for complete film synopses, parental guides, and FAQs about titles as determined by (and answered by) individual contributors.

Data format and access
IMDb does not provide an API for automated queries. However most of the data can be downloaded as compressed plain text files and the information can be extracted using the command-line interface tools provided. Beside that there is the Java based GUI application available that is able to process the compressed plain text files and allow to search and display the information. This GUI application supports different languages but the movie related data is of course English as made available by IMDb. A Python package called IMDbPY can also be used to process the compressed plain text files into a number of different SQL databases, enabling easier access to the entire dataset for searching or data mining.

Film titles
The IMDb has sites in English as well as versions translated completely or in part into other languages (Portuguese, Finnish, French, German, Hungarian, Italian, Polish, Romanian and Spanish). The non-English language sites display film titles in the specified language. While originally the IMDb's English-language sites displayed titles according to their original country-of-origin language, in 2010 the IMDb began allowing individual users in the UK and USA to choose primary title display by either the original-language titles, or the US or UK release title (normally, in English).

Censorship
IMDb.com is currently (May 2012) blocked in China. People who try to access IMDb in China directly will get a message similar to "This webpage is not available – The connection to imdb.com was interrupted." But IMDb in other languages (such as imdb.fr, imdb.de, imdb.it, etc.) are still accessible.