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Taiwan,[II][k] officially the Republic of China (ROC),[I][l] is a country[27] in East Asia.[o] It is located at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. The territories controlled by the ...
Costco Wholesale Corporation (commonly shortened to Costco) is an American multinational corporation which operates a chain of membership-only big-box warehouse club retail stores. [4] As of 2021, Costco is the third-largest retailer in the world [5] and is the world's largest retailer of choice and prime beef, organic foods, rotisserie chicken ...
- 304,000 (2022)
- September 15, 1983; 40 years ago (as Costco), Seattle, Washington, U.S.
- US$226.95 billion (2022)
- Issaquah, Washington, U.S.
YouTube is an American online video sharing platform owned by Google. Accessible worldwide, [note 1] YouTube launched on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim, three former employees of PayPal. Headquartered in San Bruno, California, United States, it is the second most visited website in the world, after Google Search.
- History
- Services
- Business Model
- Reception
- In Popular Culture
- See Also
- External Links
Early history
The idea for Duolingo was formulated in 2009 by Carnegie Mellon University professor Luis von Ahn and his Swiss-born post-graduate student Severin Hacker. Von Ahn had sold his second company, reCAPTCHA, to Google and, with Hacker, wanted to work on an education-related project. Von Ahn stated that he saw how expensive it was for people in his community in Guatemala to learn English. Hacker (co-founder and current CTO of Duolingo) believed that "free education will really change the world" and...
Funds
In October 2011, Duolingo announced that it had raised $3.3 million from a Series A round of funding, led by Union Square Ventures, with participation from author Tim Ferriss and actor Ashton Kutcher's investing firm A-Grade Investments. Duolingo launched a private beta on November 27, 2011, and accumulated a waiting list of more than 300,000 people.It launched to the general public on June 19, 2012, at which point the waiting list had grown to around 500,000. In September 2012, Duolingo anno...
Features and media
In October 2013, Duolingo launched a crowdsourced language incubator. In March 2021, it announced that it would be ending its volunteer contributor program and donating money to its volunteer contributors who helped develop it. The company said that from now on, language courses would be maintained and developed by professional linguists aligning with CEFR standards. On June 28, 2021, Duolingo filed for an initial public offering on NASDAQ under the ticker DUOL.From August 2021 to June 2022,...
Duolingo
Duolingo is an app and website that uses a gamified approach to language learning, with lessons that incorporate translating, interactive exercises, quizzes, and stories. It also uses an algorithm that adapts to each learner and can provide personalized feedback and recommendations. It offers podcastsin some languages, consisting of stories usually told by native speakers in the target language. The programs use simplified grammar and vocabulary, slower intonation, and occasional assistance w...
Duolingo ABC
Duolingo ABC is a free app designed for young children to learn letters, their sounds, phonics, and other early reading concepts. Released in 2020, it does not contain ads or in-app purchases. As of April 2024, iOS and Android versions are available, but only in English and Spanish.
Duolingo Math
Duolingo Math is a course for learning elementary mathematics. It is currently only available on iOS devices in English and Spanish.
Duolingo had revenue of $1 million in 2016, $13 million in 2017, $36 million in 2018, and $250.77 million in 2021. In May 2022, it was reported that 6.8% of its monthly active users paid for the ad-free version of the app. Duolingo has derived most of its revenue from subscriptions, advertising, and its Duolingo English Test. In April 2020, it pass...
Effectiveness
A 2017 study found no significant difference between elementary students learning Spanish through the "gamification" of Duolingo and those learning in classroom environments, with both groups demonstrating a similar increase in achievements and self-efficacy. A 2022 study on adults using Duolingo as their only language learning tool, published in the journal Foreign Language Annals, found that the participants that completed a course had similar reading and listening proficiency to university...
Criticism
Some language professionals have criticized its app for its limitations and gamified design. Others have pointed out that Duolingo and similar apps can be a starting point but lack the human interaction required to be fluent in a language and for real-life conversations.Players have also reported that "gamification" has led to cheating, hacking, and incentivized game strategies that conflict with actual learning. Since the end of October 2023, Duolingo has decided to stop updating its Welsh c...
Awards
In 2013, Apple chose Duolingo as its iPhone App of the Year, a first for an educational application. That year, Duolingo ranked No. 7 on Fast Company's "The World's Most Innovative Companies: Education Honorees" list "for crowdsourcing web translation by turning it into a free language-learning program". Duolingo won Best Education Startup at the 2014 Crunchies, and was the most downloaded 'education app' in Google Play in 2013 and 2014. In July 2020, PCMagnamed it "The Best Free Language Lea...
Due to the app's frequent reminder notifications, Duolingo's mascot, a green cartoon owl named Duo, has been the subject of Internet memes where the mascot is "evil" and stalks and threatens users if they do not keep using the app—with the tongue-in-cheekthreat indicating physical harm to the user and/or their family for failing to continue their l...
Business data for Duolingo, Inc.:Belgium,[A] officially the Kingdom of Belgium,[B] is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the south, and the North Sea to the west. It covers an area of 30,689 km2 (11,849 sq mi)[4][12] and has a population of more than 11.5 ...
Georgia is a mountainous country situated almost entirely in the South Caucasus, while some slivers of the country are situated north of the Caucasus Watershed in the North Caucasus. [164] [165] The country lies between latitudes 41° and 44° N, and longitudes 40° and 47° E, with an area of 67,900 km 2 (26,216 sq mi).
Kazakhstan, [b] officially the Republic of Kazakhstan, [c] is a landlocked country mostly in Central Asia, with a part in Eastern Europe. [d] It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbekistan to the south, and Turkmenistan to the southwest, with a coastline along the Caspian Sea.
