Recommender systems

YouTube is an American online video sharing platform owned by Google. YouTube was founded on February 14, 2005, by Chad Hurley, Jawed Karim, and Steve Chen, who were former employees of PayPal. Headquartered in San Bruno, California, it is the second-most-visited website in the world, after Google itself. In January 2024, YouTube had reached more than 2.7billion monthly active users, who collectively consumed more than one billion hours of video content every day. , videos were being uploaded to the platform at a rate of more than 500 hours of content per minute, and , there were approximately

IMDb, formerly known as the Internet Movie Database, is an online database of information related to films, television series, podcasts, video games, and streaming content online – including cast, production crew and biographies, plot summaries, trivia, ratings, and fan and critical reviews. As of September 2025, IMDb ranks as the 40th most visited website in the world and the 35th in the United States.

American review aggregator for film and television

Last.fm is a music website founded in the United Kingdom in 2002. Utilizing a music recommender system known as "Audioscrobbler", Last.fm creates a detailed profile of each user's musical preferences by recording the details of the tracks they listen to, whether from Internet radio stations or from the user's computer or portable music devices. This information is transferred ("scrobbled") to Last.fm's database via the music player (such as Spotify and Apple Music) or through a plug-in installed in the user's music player. The data is then displayed on the user's profile page and compiled to c

Metacritic is an American website that aggregates reviews of films, television shows, music albums, video games, and formerly books. For each product, the scores from each review are averaged (a weighted average). Metacritic was created by Jason Dietz, Marc Doyle, and Julie Doyle Roberts in 1999, and was acquired by Fandom, Inc. in 2022.

information filtering system to predict users' preferences

system that supports business or organizational decision-making processes

theory in economics

Yelp Inc. is an American company that develops the Yelp.com website and the Yelp mobile app, which publishes crowd-sourced reviews about businesses. It also operates Yelp Guest Manager, a table reservation service. It is headquartered in San Francisco.

American music streaming and recommendation website

Personalization (broadly known as customization) consists of tailoring a service or product to accommodate specific individuals. It is sometimes tied to groups or segments of individuals. Personalization involves collecting data on individuals, including web browsing history, web cookies, and location. Various organizations use personalization (along with the opposite mechanism of popularization) to improve customer satisfaction, digital sales conversion, marketing results, branding, and improved website metrics as well as for advertising. Personalization acts as a key element in social media

algorithm

FilmAffinity is a movie recommendations website created in 2002 in Madrid, Spain, by the film critic Pablo Kurt Verdú Schumann and the programmer Daniel Nicolás. In 2016, the site listed 125,000 movies and series and had 556,000 reviews written by its users.

personal recommendations service owned by Russia's VK

RhythmOne , a subsidiary of Nexxen, is an American digital advertising technology company that owns and operates the web properties AllMusic, AllMovie, and SideReel.

nonprofit organization based in San Francisco, United States

free TV series tracking service

Outbrain is a web recommendation platform founded in 2006 by co-founder and Co-CEO Yaron Galai and co-founder, Chief Technology Officer and General Manager, Ori Lahav. The company is headquartered in New York City.

Russian streaming service

Songza was a free music streaming and recommendation service for Internet users in the United States and Canada.

set of categories designed to elicit information about a quantitative or a qualitative attribute

concept in information systems