Meta Platforms, Inc., doing business as Meta, and formerly named Facebook, Inc., and TheFacebook, Inc., is an American multinational technology conglomerate based in Menlo Park, California. The company owns and operates Facebook, Instagram, Threads, and WhatsApp, among other products and services. Advertising accounts for 97.8 percent of its revenue 2023. Meta ranks among the largest American information technology companies, alongside other Big Five corporations Alphabet (Google), Amazon, Apple, and Microsoft. The company was ranked #31 on the Forbes Global 2000 ranking in 2023. In 2022, Meta was the company with the third-highest expenditure on research and development worldwide, with R&D expenditure amounting to US$35.3 billion.

Meta has also acquired Oculus (which it has integrated into Reality Labs), Mapillary, CTRL-Labs, and a 9.99% stake in Jio Platforms; the company additionally endeavored into non-VR hardware, such as the discontinued Meta Portal smart displays line and partners with Luxottica through the Ray-Ban Stories series of smartglasses.

Parent company Facebook, Inc. rebranded as Meta Platforms, Inc. on October 28, 2021, to "reflect its focus on building the metaverse", an integrated environment linking the company's products and services.

Twitter, Inc. was an American social media company based in San Francisco, California, which operated and was named for its flagship social media network prior to its rebrand as X. In addition to Twitter, the company previously operated the Vine short video app and Periscope livestreaming service. In April 2023, Twitter merged with X Holdings and ceased to be an independent company, becoming a part of X Corp.

Twitter was created by Jack Dorsey, Noah Glass, Biz Stone, and Evan Williams in March 2006 and was launched that July. By 2012, more than 100 million users tweeted 340 million tweets a day. The company went public in November 2013. By 2019, Twitter had more than 330 million monthly active users.

On April 25, 2022, Twitter agreed to a $44 billion buyout by Elon Musk, CEO of SpaceX and Tesla, one of the biggest deals to turn a company private. On July 8, Musk terminated the deal. Twitter's shares fell, leading company officials to sue Musk in Delaware's Court of Chancery on July 12. On October 4, Musk announced his intention to purchase the company as he had agreed, for $44 billion, or $54.20 a share; the agreement closed on October 27.

Following Musk's takeover, Twitter was criticized for an increase in hate speech, as well as for perceived systemic prioritization of right-wing content. His acquisition of the company has been characterized by large-scale policy changes, mass layoffs and resignations, and a dramatic shift in the company's work culture.

Pinterest is an American social media service for publishing and discovery of information in the form of pinboards. This includes recipes, home, style, motivation, and inspiration on the Internet using image sharing. Pinterest, Inc. was founded by Ben Silbermann, Paul Sciarra, and Evan Sharp, and is headquartered in San Francisco.

LinkedIn (/lɪŋktˈɪn/) is a business and employment-focused social media platform that works through websites and mobile apps. It was launched on May 5, 2003 by Reid Hoffman and Eric Ly. Since December 2016, LinkedIn has been a wholly owned subsidiary of Microsoft. The platform is primarily used for professional networking and career development, and allows jobseekers to post their CVs and employers to post jobs. From 2015, most of the company's revenue came from selling access to information about its members to recruiters and sales professionals. LinkedIn has more than 1 billion registered members from over 200 countries and territories.

LinkedIn allows members (both employees and employers) to create profiles and connect with each other in an online social network which may represent real-world professional relationships. Members can invite anyone (whether an existing member or not) to become a connection. LinkedIn can also be used to organize offline events, join groups, write articles, publish job postings, post photos and videos, and more.

WhatsApp (officially WhatsApp Messenger) is an instant messaging (IM) and voice-over-IP (VoIP) service owned by technology conglomerate Meta. It allows users to send text, voice messages and video messages, make voice and video calls, and share images, documents, user locations, and other content. WhatsApp's client application runs on mobile devices, and can be accessed from computers. The service requires a cellular mobile telephone number to sign up. In January 2018, WhatsApp released a standalone business app called WhatsApp Business which can communicate with the standard WhatsApp client.

The service was created by WhatsApp Inc. of Mountain View, California, which was acquired by Facebook in February 2014 for approximately US$19.3 billion. It became the world's most popular messaging application by 2015, and had more than 2 billion users worldwide by February 2020, confirmed four years later by new 200M registrations per month. By 2016, it had become the primary means of Internet communication in regions including the Americas, the Indian subcontinent, and large parts of Europe and Africa.

Messenger, also known as Facebook Messenger, is an American proprietary instant messaging service developed by Meta Platforms. Originally developed as Facebook Chat in 2008, the client application of Messenger is currently available on iOS and Android mobile platforms, Windows and macOS desktop platforms, through the Messenger.com web application, and on the standalone Facebook Portal hardware.

Messenger is used to send messages and exchange photos, videos, stickers, audio, and files, and also react to other users' messages and interact with bots. The service also supports voice and video calling. The standalone apps support using multiple accounts, conversations with end-to-end encryption, and playing games.

WeChat or Weixin in Chinese (Chinese: 微信; pinyin: Wēixìn (listenⓘ); lit. 'micro-message') is a Chinese instant messaging, social media, and mobile payment app developed by Tencent. First released in 2011, it became the world's largest standalone mobile app in 2018 with over 1 billion monthly active users. WeChat has been described as China's "app for everything" and a super-app because of its wide range of functions. WeChat provides text messaging, hold-to-talk voice messaging, broadcast (one-to-many) messaging, video conferencing, video games, mobile payment, sharing of photographs and videos and location sharing.

Accounts registered using Chinese phone numbers are managed under the Weixin brand, and their data is stored in mainland China and subject to Weixin's terms of service and privacy policy, which forbids content which "endanger national security, divulge state secrets, subvert state power and undermine national unity". Non-Chinese numbers are registered under WeChat, and WeChat users are subject to a different, less strict terms of service and stricter privacy policy, and their data is stored in the Netherlands for users in the European Union, and in Singapore for other users. User activity on Weixin, the Chinese version of the app, is analyzed, tracked and shared with Chinese authorities upon request as part of the mass surveillance network in China. Chinese-registered Weixin accounts censor politically sensitive topics. Any interactions between Weixin and WeChat users are subject to the terms of service and privacy policies of both services.

Viber, or Rakuten Viber, is a cross-platform voice over IP (VoIP) and instant messaging (IM) software application owned by Japanese multinational company Rakuten, provided as freeware for the Google Android, iOS, Microsoft Windows, Apple macOS and Linux platforms. Users are registered and identified through a cellular telephone number, although the service is accessible on desktop platforms without needing mobile connectivity. In addition to instant messaging it allows users to exchange media such as images and video records, and also provides a paid international landline and mobile calling service called Viber Out. As of 2018, there are over a billion registered users on the network.

The software was developed in 2010 by Cyprus-based Viber Media, which was bought by Rakuten in 2014. Since 2017, its corporate name has been Rakuten Viber. It is based in Cyprus with offices in London, Manila, Moscow, Paris, San Francisco, Singapore, Tokyo, and Beijing.

Line is a freeware app and service for instant messaging and social networking, operated by the Japanese company LY Corporation, co-owned by SoftBank Group. Line was launched in Japan in June 2011 by NHN Japan, a subsidiary of Naver.

Initially designed for text messaging and VoIP voice and video calling, it has gradually expanded to become a super-app providing services including a digital wallet (Line Pay), news stream (Line Today), video on demand (Line TV) and digital comic distribution (Line Manga and Line Webtoon). Line became Japan's largest social network in 2013 and is used by over 70% of the population as of 2023; it is also popular mainly in Indonesia, Taiwan and Thailand.

KakaoTalk (Korean: 카카오톡), commonly referred to as KaTalk (Korean: 카톡) in South Korea, is an instant messenger and online services platform operated by Kakao Corporation. It was launched in 2010 and the app is available on mobile and desktop platforms. Originally designed for messaging, it has evolved into becoming a super-app providing mobile payments and banking, taxi hailing, games and others.

As of August 2022, KakaoTalk had 53 million monthly active users, 47 million inside Korea. It is available in 15 languages. The app is used by 93% of smartphone owners in South Korea, where it is the most widely used instant messenging app. After the COVID-19 pandemic, it has further grown in prominence after becoming widely used as a tool to combat COVID-19, in cooperation with the South Korean government.

Telegram Messenger, commonly known as Telegram, is a cloud-based, cross-platform, social media and instant messaging (IM) service. It was originally launched for iOS on 14 August 2013 and Android on 20 October 2013. It allows users to exchange messages, share media and files, and hold private and group voice or video calls as well as public livestreams. It is available for Android, iOS, Windows, macOS, Linux, and web browsers. Telegram offers end-to-end encryption in voice and video calls, and in optional private chats, which Telegram calls Secret Chats.

Telegram also has social networking features, allowing users to post stories, create large public groups with up to 200,000 members, or share one-way updates to unlimited audiences in so-called channels.

Telegram was founded in 2013 by Nikolai and Pavel Durov. Its servers are distributed worldwide with several data centers, while the headquarters is in Dubai, United Arab Emirates. Telegram is the most popular instant messaging application in parts of Europe, Asia, and Africa. As of 2024, registration to Telegram requires either a smartphone or one of a limited number of NFTs issued in December 2022.

As of July 2024, Telegram has more than 950 million monthly active users, with India leading in the number of users. It was the most downloaded app worldwide in January 2021 with 1 billion downloads globally as of late August 2021.

Tencent QQ (Chinese: 腾讯QQ), also known as QQ, is an instant messaging software service and web portal developed by the Chinese technology company Tencent. QQ offers services that provide online social games, music, shopping, microblogging, movies, and group and voice chat software. As of March 2023, there were 597 million monthly active QQ accounts.

Snapchat is an American multimedia instant messaging app and service developed by Snap Inc., originally Snapchat Inc. One of the principal features of the multimedia Snapchat is that pictures and messages are usually available for only a short time before they become inaccessible to their recipients. The app has evolved from originally focusing on person-to-person photo sharing to presently featuring users' "Stories" of 24 hours of chronological content, along with "Discover", letting brands show ad-supported short-form content. It also allows users to store photos in a password-protected area called "My Eyes Only". It has also reportedly incorporated limited use of end-to-end encryption, with plans to broaden its use in the future.

Snapchat was created by Evan Spiegel, Bobby Murphy, and Reggie Brown, former students at Stanford University. It is known for representing a mobile-first direction for social media, and places significant emphasis on users interacting with virtual stickers and augmented reality objects. In July 2021, Snapchat had 293 million daily active users, a 23% growth over a year. On average more than four billion Snaps are sent each day. Snapchat is popular among the younger generations, particularly those below the age of 16, leading to many privacy concerns for parents.

Short Message Service, commonly abbreviated as SMS, is a text messaging service component of most telephone, Internet and mobile device systems. It uses standardized communication protocols that let mobile phones exchange short text messages, typically transmitted over cellular networks.

Developed as part of the GSM standards, and based on the SS7 signalling protocol, SMS rolled out on digital cellular networks starting in 1993 and was originally intended for customers to receive alerts from their carrier/operator. The service allows users to send and receive text messages of up to 160 characters, originally to and from GSM phones and later also CDMA and Digital AMPS; it has since been defined and supported on newer networks, including present-day 5G ones. Using SMS gateways, messages can be transmitted over the Internet through an SMSC, allowing communication to computers, fixed landlines, and satellite. MMS was later introduced as an upgrade to SMS with "picture messaging" capabilities.

In addition to recreational texting between people, SMS is also used for mobile marketing (a type of direct marketing), two-factor authentication logging-in, televoting, mobile banking (see SMS banking), and for other commercial content. The SMS standard has been hugely popular worldwide as a method of text communication: by the end of 2010, it was the most widely used data application with an estimated 3.5 billion active users, or about 80% of all mobile phone subscribers. More recently, SMS has become increasingly challenged by newer proprietary instant messaging services; RCS has been designated as the potential open standard successor to SMS.

Threads is an online social media and social networking service operated by Meta Platforms. The service features integration with Instagram and users must register for Threads with an Instagram account. Functionally it is similar to Twitter: users can post text, images, voice recordings, and videos, as well as interact with other users' posts through replies, reposts, and likes. The application is available on iOS and Android devices; the web version offers limited functionality and requires a mobile app to be installed first. Upon its launch, Threads became the fastest-growing consumer software application in history, gaining over 100 million users in its first five days and surpassing the record previously set by ChatGPT. This early success was not sustained, and the user base of the app plummeted more than 80% to 8 million daily active users by the end of July 2023.

Threema is a paid cross-platform encrypted instant messaging app developed by Threema GmbH in Switzerland and launched in 2012. The service operates on a decentralized architecture and offers end-to-end encryption. Users can make voice and video calls, send photos, files, and voice notes, share locations, and make groups. Unlike many other popular secure messaging apps, Threema does not require phone numbers or email addresses for registration, only a one-time purchase that can be paid via an app store or anonymously with Bitcoin or cash. Threema is available on iOS and Android, and has clients for Windows, macOS, Linux, and HarmonyOS and can be accessed via web browser but requires a mobile app to function.

Bluesky is a microblogging social media service. Users can share short posts containing text, images, and videos. It is owned by Bluesky Social PBC, a benefit corporation based in the United States.

Bluesky was developed as a reference implementation of the AT Protocol, an open communication protocol for distributed social networks. Bluesky Social promotes a composable user experience and algorithmic choice as core features of Bluesky. The platform offers a "marketplace of algorithms" where users can choose or create algorithmic feeds, user-managed moderation and labelling services, and user-made "starter packs" that allow users to quickly follow a large number of related accounts within a community or subculture. The AT Protocol offers a domain-name–based handle system within Bluesky, allowing users to self-verify an account's legitimacy and identity by proving ownership of a domain name.

Bluesky began in 2019 as a research initiative at Twitter, becoming an independent company in 2021. Development for the social app accelerated in 2022 after Elon Musk's acquisition of Twitter and subsequent severing of ties between the companies. Bluesky launched as an invite-only service in February 2023 and opened registrations in February 2024. Former Twitter CEO Jack Dorsey left Bluesky Social's board by May 2024. The social media platform grew after October 2024, reaching 20 million users by November 2024 and 30 million by January 2025.

Mastodon is a free and open-source software platform for decentralized social networking with microblogging features similar to Twitter. It operates as a federated network of independently managed servers that communicate using the ActivityPub protocol, allowing users to interact across different instances within the Fediverse. Each Mastodon instance establishes its own moderation policies and content guidelines, distinguishing it from centrally controlled social media platforms.

First released in 2016 by Eugen Rochko, Mastodon has positioned itself as an alternative to mainstream social media, particularly for users seeking decentralized, community-driven spaces. The platform has experienced multiple surges in adoption, most notably following the Twitter acquisition by Elon Musk in 2022, as users sought alternatives to Twitter. It is part of a broader shift toward decentralized social networks, including Bluesky and Lemmy.

Mastodon emphasizes user privacy and moderation flexibility, offering features such as granular post visibility controls, content warning options, and local community-driven moderation. The software is written in Ruby on Rails and Node.js, with a web interface built using React and Redux. It is interoperable with other ActivityPub-based platforms, such as Threads, and supports various third-party applications on desktop and mobile devices.