Duolingo

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Duolingo, Inc.
Duolingo 2019.png
Screenshot
Duolingo homepage.png
Duolingo homepage
Type of businessPrivate
Available in
HeadquartersPittsburgh, Pennsylvania, United States
Area servedWorld
Founder(s)Luis von Ahn, Severin Hacker
CEOLuis von Ahn
IndustryOnline education, Professional certification, Translation, Crowdsourcing
ServicesLanguage courses, Duolingo English Test, Duolingo for Schools, Tinycards flashcard app
Revenue36 million USD in 2018[1]
Employees170[1]
Websitewww.duolingo.com
Alexa rankIncrease 729 (June 2019)[4]
AdvertisingYes
RegistrationYes
Users±300 million people[5]
Launched30 November 2011; 7 years ago (2011-11-30) (private beta)
19 June 2012; 7 years ago (2012-06-19) (public release)
Current statusOnline
Native client(s) onAndroid, iOS, Windows Phone, Windows 10 Mobile
Written inSwift,[2] React, Python, Scala[3]

Duolingo (/ˌdˈlɪŋɡ/ DOO-oh-LING-goh) is a platform that includes a language-learning website and app, as well as a digital language proficiency assessment exam. The company uses the freemium model; the app and the website are accessible without charge, although Duolingo also offers a premium service for a fee. As of August 2019 the language-learning website and app offer 90 different language courses in 22 languages. The app has over 300 million registered users across the world.[6][7][8][9][10]

History[edit]

The project was started at the end of 2009 in Pittsburgh by Carnegie Mellon University professor Luis von Ahn (creator of reCAPTCHA) and his graduate student Severin Hacker, and then developed along with Antonio Navas, Vicki Cheung, Marcel Uekermann, Brendan Meeder, Hector Villafuerte, and Jose Fuentes.[11][12]

Inspiration for Duolingo came from two places. Luis Von Ahn wanted to create another program that served two purposes in one, what he calls a "twofer".[13] Duolingo originally did this by teaching its users a foreign language while having them translate simple phrases in documents, though the translation feature has since been removed.[14]

Von Ahn was born in Guatemala and saw how expensive it was for people in his community to learn English. Severin Hacker (born in Zug, Switzerland), co-founder of Duolingo, and Von Ahn believe that "free education will really change the world"[15] and wanted to supply people an outlet to do so.

The project was originally sponsored by Luis von Ahn's MacArthur fellowship and a National Science Foundation grant.[16][17] Additional funding was later received in the form of investments from Union Square Ventures and actor Ashton Kutcher's firm, A-Grade Investments.[18][19]

Duolingo started its private beta on 30 November 2011, and accumulated a waiting list of more than 300,000 users.[20] On 19 June 2012, Duolingo launched for the general public. Owing to popular interest, Duolingo has received many investments including a $20 million Series C round of investment led by Kleiner Caufield & Byers and a $45 million Series D round of investment led by Google Capital.[21] As of 2019, Duolingo has 170 staff members,[1] of whom many were Google employees,[22] and operates from an office in the Pittsburgh neighborhood of East Liberty.[23][24][25]

On 13 November 2012, Duolingo released their iOS app through the iTunes App Store.[26] The application is a free download and is compatible with most iPhone, iPod and iPad devices.[27] On 29 May 2013, Duolingo released their Android app, which was downloaded about a million times in the first three weeks and quickly became the #1 education app in the Google Play store.[28] As of 2017, the company had a total funding of US$108.3 million.[29] Duolingo received a fifth-round $25 million in July 2017 from Drive Capital, with the funds directed toward creating initiatives such as TinyCards and Duolingo Labs.[30] Duolingo reached a revenue of $13 million in 2017 and $36 million in 2018.[1]

Business model[edit]

All language-learning features in Duolingo are free of charge, but it uses periodic advertising in both its mobile and web browser applications,[31][32] which users can remove by paying a subscription fee. It originally employed a crowd sourced business model, where the content came from organizations (such as CNN and BuzzFeed) that paid Duolingo to translate it.[33]

Duolingo is funded by Union Square Venture Partners ($3.3 million in 2011), New Enterprise Associates ($15 million), Kleiner Perkins Caufield & Byers ($20 million), Google Capital ($45 million), Ashton Kutcher's A-Grade Investments, and Tim Ferriss.[34][35][36]

Language courses[edit]

Courses for English speakers[edit]

As of 16 November 2019, 34 courses are available to the public in English, three of which are constructed languages, and those three include two fictional languages.[37][38][39] In this list, the courses are ordered by number of active learners.

Complete
Beta
Alpha

As of August 2019, four courses for English speakers are in development (ordered by progression percentage towards completion according to the Weekly Incubator Update[45])

Courses unavailable in English[edit]

Duolingo offers language courses for speakers of languages other than English, but all available languages offer at least English as a course. The Catalan and Guarani courses are exclusive to Spanish speakers.

Courses available in other languages[edit]

As of 28 August 2019, the following languages are available to speakers of languages other than English:[50]

(#) = course still in development (β) = Course still in beta version

Number of languages
available for speakers of:
On app On website
German 3 3
Turkish 3 4
Spanish 9 9
Greek 1 1
Dutch 1 1
French 5 5
Hungarian 1 1
Czech 1 1
Italian 3 4
Arabic 4 5
Indonesian 1 1
Korean 1 1
Ukrainian 1 1
Vietnamese 1 1
Japanese 1 1
Russian 4 5
Thai 1 1
Hindi 1 1
Chinese 6 6
Portuguese 6 6
Polish 1 1
Romanian 1 1
Bengali 1
Punjabi 1
Tagalog 1
Tamil 1
Telugu 1

List of courses by number of learners[edit]

As of 16 September 2019:

Rank Language taught For Speakers of Number of Learners
1 English Spanish 27,700,000
2 Spanish English 23,400,000
3 French English 13,300,000
4 English Portuguese 10,700,000
5 German English 7,600,000
6 Japanese English 6,070,000
7 English Russian 5,650,000
8 Italian English 5,200,000
9 English Arabic 4,360,000
10 English French 4,240,000
11 French Spanish 3,950,000
12 Korean English 3,630,000
13 Chinese English 3,470,000
14 Russian English 3,120,000
15 English Turkish 2,980,000
16 English Chinese 2,760,000
17 Spanish Portuguese 2,640,000
18 Italian Spanish 2,450,000
19 English German 2,300,000
20 English Vietnamese 2,260,000
21 Portuguese English 2,220,000
22 English Italian 2,130,000
23 Portuguese Spanish 2,090,000
24 English Hindi 1,870,000
25 English Polish 1,630,000
26 German Spanish 1,610,000
27 Turkish English 1,430,000
28 French Portuguese 1,410,000
29 Spanish French 1,400,000
30 Dutch English 1,330,000
31 English Indonesian 1,160,000
33 Swedish English 1,150,000
32 English Japanese 1,130,000
33 Hindi English 1,090,000
34 Spanish German 1,080,000
35 Greek English 1,050,000
36 High Valyrian English 1,000,000
38 English Romanian 955,000
39 Irish English 939,000
40 German Russian 877,000
42 English Dutch 863,000
41 Polish English 863,000
43 Hebrew English 834,000
44 Norwegian (Bokmål) English 825,000
45 English Czech 759,000
46 French German 749,000
47 Italian Portuguese 748,000
48 Arabic English 725,000
49 Russian Spanish 715,000
50 French Arabic 714,000
52 English Hungarian 709,000
51 German Portuguese 706,000
53 Catalan Spanish 688,000
54 English Korean 650,000
55 French Russian 635,000
56 Vietnamese English 591,000
57 Hawaiian English 570,000
58 Italian French 552,000
59 Spanish Russian 551,000
60 German French 539,000
61 English Ukrainian 533,000
63 German Turkish 523,000
62 Danish English 517,000
65 Romanian English 449,000
66 Spanish Chinese 436,000
64 Klingon English 435,000
67 Czech English 414,000
68 German Arabic 378,000
69 French Italian 372,000
70 Indonesian English 367,000
71 Swahili English 363,000
72 Welsh English 363,000
73 English Thai 331,000
74 Japanese Chinese 330,000
75 Navajo English 327,000
76 Hungarian English 321,000
77 Ukrainian English 318,000
78 German Italian 317,000
79 Esperanto English 302,000
80 Russian Turkish 290,000
81 Esperanto Spanish 284,000
82 Guarani (Jopará) Spanish 283,000
83 Portuguese French 274,000
84 English Greek 261,000
85 Esperanto Portuguese 240,000
86 Korean Chinese 204,000
87 Latin English 150,000
88 Swedish Arabic 149,000
89 French Chinese 101,000
90 Spanish Italian 67,500
91 Italian Chinese 36,900
92 Swedish Spanish 100% complete, not released, estimated 22 September 2019[60]
93 Swedish Russian 84% complete, not released, estimated 14 July 2020[61]
94 English Bengali 72% complete, not released, estimated 29 November 2019[62]
95 English Tamil 70% complete, not released, estimated 2 October 2019[63]
96 French Turkish 68% complete, not released, estimated 21 June 2021[64]
97 Spanish Arabic 65% complete, not released, estimated 1 September 2019[65]
98 Chinese Japanese 60% complete, not released, estimated 18th October 2019[66]
98 German Chinese 50% complete, not released, estimated 30 June 2020[67]
99 German Dutch 48% complete, not released, estimated 24 December 2019[68]
100 English Tagalog 41% complete, not released, estimated 1 September 2020[69]
101 English Punjabi (Gurmukhi) 26% complete, not released, estimated 8 July 2019[70]
102 English Telugu 21% complete, not released, estimated 25 December 2019[71]

List of Courses being created[edit]

As of October 2019, 17 courses are currently being developed on Duolingo[72]

Rank by

Estimated

Completion

Teaching For...Speakers Percent completed[73] Estimated

completion date

(yyyy/mm/dd)

1 Swedish Spanish 100% 2019/09/22 - 22 September 2019[74]
2 Scottish Gaelic English 100% 2020/7/17 - 17 July 2020[75]
3 English Bengali 80% 2019/11/29 - 29 November 2019[76]
4 English Tamil 73% 2019/10/2 - 2 October 2019[77]
5 Swedish Russian 66% 2020/7/26 - 26 July 2020[78]
6 English Tagalog 49% 2020/9/1 - 1 September 2020[79]
7 German Dutch 39% 2019/12/24 - 24 December 2019[80]
8 English Punjabi (Gurmakhi) 29% 2019/7/8 - 8 July 2019[81]
9 French Turkish 28% 2021/7/5 - 5 July 2021[82]
10 Yiddish English 26% 2018/7/7 - 7 July 2018[83]
11 Spanish Arabic 23% 2099/12/31 - 31 December 9999[84]
12 English Telugu 22% 2019/12/25 - 25 December 2019[85]
13 Haitian Creole English 17% 2019/12/31 - 31 December 2019[86]
14 Finnish English 2% 2020/4/1 - 1 April 2020[87]
15 Chinese Japanese 0% 2019/11/1 - 1 November 2019[88]
16 Swedish Turkish 0% 2020/3/15 - 15 March 2020[89]
17 German Chinese 0% 2020/6/30 - 30 June 2020[90]

Features[edit]

Presentation at Wikimania about Duolingo.

Duolingo mimics the structure of video games in several ways in order to engage its users. There is a reward system in which users acquire "lingots", an in-game currency that can be spent on features such as character customizations or bonus levels (both available on the mobile app only). There are public leaderboards in which people can compete against their friends or see how they stack up against the rest of the world. The level system that Duolingo uses is XP (experience points), a numerical system that represents a user's skill level. Badges in Duolingo represent achievements that are earned from completing specific objectives or challenges.[91]

Duolingo Leaderboards[edit]

Duolingo Clubs was launched on 20 December 2016, with the intention of promoting competitiveness and relations between users, adding more "fun" to the course, which increases learning motivation. In Duolingo Clubs there is a weekly ranking of the experience acquired in the lessons, there are badges (achievements) to acquire, among other implements. Duolingo Clubs are available on the mobile versions of iOS, Android and Windows Phone. Although it has a very similar system, it is not completely identical to the website.[92] In May 2019, Duolingo Clubs was replaced by Duolingo Leaderboards, of which there are ten: Bronze, Silver, Gold, Sapphire, Ruby, Emerald, Amethyst, Pearl, Obsidian and Diamond, in that increasing order. To get to the next league, the user has to rank in the top 10 out of 50 in a weekly XP race.

Use in schools[edit]

Duolingo provides "Duolingo for Schools" with features designed to allow teachers to track their students. In 2012, an effectiveness study concluded that Duolingo usage for Spanish study was more effective than classroom language learning alone, but that it was less effective for advanced language learners.[93] One proposed reason for this is that the direct-translation method that Duolingo primarily uses is more applicable to simple words and phrases than to complex ones; simpler ones can be translated in a more exact manner from one language to another and thus are more conducive to Duolingo's direct-translation method.[94]

Infrastructure[edit]

Duolingo uses many services in the Amazon Web Services suite of products, including Amazon DynamoDB, Amazon Virtual Private Cloud, nearly 200 virtual instances in Amazon Elastic Compute Cloud (EC2), Amazon Simple Storage Service (S3) and Amazon Relational Database Service (RDS).[95] The server backend is written in the programming language Python.[better source needed] A component called the Session Generator was rewritten in Scala by 2017.[3] The frontend was written in Backbone.js and Mustache but is now primarily in React and Redux. Duolingo provides a single-page web application for desktop computer users and also smart phone applications on Android (both Google Play Store and Amazon Appstore), iOS App Store and Windows Phone platforms. 20% of traffic comes from desktop users and 80% from mobile app users.[95]

In popular culture[edit]

Duolingo's mascot, a green cartoon owl named Duo, has been a subject of an Internet meme in which the mascot will stalk and threaten users if they do not keep using the app.[96] Acknowledging the meme, Duolingo released a video on April 1 2019 as an April Fools' Day joke; the video depicts a fictitious new premium feature called "Duolingo Push". According to the video, users of "Duolingo Push" will receive reminders to use the app in person by Duo himself, who stares at users and follows them around until they use the app (in the video, Duo is depicted by a person in a large mascot costume.)[97][98]

Recognition and awards[edit]

In 2013, Apple chose Duolingo as its iPhone App of the Year, the first time this honor had been awarded to an educational application.[99] Also, Duolingo won Best Education Startup at the 2014 Crunchies,[23] and was the most downloaded app in the Education category in Google Play in 2013 and 2014.[100] In 2015, Duolingo was announced the 2015 award winner in Play & Learning category by Design to Improve Life.[101] In 2018, Duolingo was named to Fast Company's list of the Most Innovative Companies[102] to CNBC's Disruptor 50 list[103] and one of TIME Magazine's 50 Genius Companies.[104] In 2019, Duolingo was named one of Forbes's "Next Billion-Dollar Startups 2019".[105]

Awards for the company[edit]

The company has also been nominated for several awards. It won Inc. magazine's Best Workplaces 2018,[106] Entrepreneur magazine's Top Company Culture List 2018,[107] Fast Company's Most Innovative Companies award in 2013, 2017 and 2018,[108] and appeared in CNBC's "Disruptor 50" list in 2019.[109]

See also[edit]

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External links[edit]