Signal is a non-profit, private messaging app founded by Moxie Marlinspike. It allows users to exchange texts and voice messages, make calls, send photos and videos, and communicate in group chats via smartphone or desktop app. Every Signal conversation is protected with end-to-end encryption, so data is only viewable to chat participants. Signal's "disappearing messages" feature lets users set a time period for how long their messages remain visible before deletion. Requiring a phone number has caused privacy concerns among some users. High-profile users include Edward Snowden, social justice organizers, journalists, and government officials. Unlike WhatsApp and most email providers, Signal can't supply user data to law enforcement, other than when the app was downloaded and last used.

What can you do with the Signal app?

With the Signal app, operated by the nonprofit Signal Foundation, you can exchange text and voice messages, make voice and video calls, and send photos and videos. You can also communicate in group chats using a smartphone or desktop app. Every conversation on Signal is protected by end-to-end encryption, so data is only viewable to chat participants. With Signal’s disappearing messages feature, users can set a time period for how long their messages remain visible before they are deleted from the chat. Because Signal cannot view or audit messages, it has avoided some of the criticism faced by Telegram.

How does Signal help keep messages private?

Signal employs end-to-end encryption to ensure that only the participants in a chat can view the data. Every conversation on Signal is protected by this encryption method. Additionally, Signal offers a "disappearing messages" feature, allowing users to set a time frame for how long messages remain visible before they are automatically deleted from the chat for all participants. Unlike WhatsApp, which has faced criticism for sharing user data with Facebook, Signal is unable to provide user information to law enforcement, except for when the app was downloaded and last used. This strengthens its privacy stance compared to competitors like Telegram, where only specifically marked "secret" chats have end-to-end encryption.

What is end-to-end encryption in Signal?

Signal is a private messaging app that uses end-to-end encryption to secure all communications. This means that every conversation on Signal is protected, and data is viewable only to the participants in the chat. Unlike other messaging apps like Telegram, where only chats marked "secret" are encrypted, Signal applies end-to-end encryption to all chats by default. This ensures that no third party, including Signal itself, can view or audit the messages.

How is Signal different from other messaging apps like WhatsApp or Messenger?

Signal distinguishes itself from other messaging apps like WhatsApp and Messenger through its focus on privacy. Every conversation on Signal is protected with end-to-end encryption, ensuring that only the participants can view the data. A key feature of Signal is the "disappearing messages" option, which allows users to set a time frame for messages to remain visible before they are deleted from the chat for all participants. While WhatsApp also uses end-to-end encryption, it has faced scrutiny for sharing user data with its parent company, Meta, for targeted advertising. Unlike Telegram, where only chats marked "secret" have end-to-end encryption, Signal applies it to all communications.

Who created Signal, and why do some people choose it for their communications?

Moxie Marlinspike (pseudonym for Matthew Rosenfeld) created Signal. He served as CEO of the Signal Foundation, a nonprofit organization, from 2015 to 2022. Signal employs end-to-end encryption, ensuring only participants can view data. Its "disappearing messages" feature lets users set time limits for message visibility, enhancing privacy. Edward Snowden and others use Signal because of these features. Social justice organizers, journalists, and government officials also use it for secure communication.

Signal

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Edward Snowden Edward Snowden, pictured in 2013, who formerly worked for the National Security Agency (NSA), has claimed to use Signal every day.

Signal

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Meg Matthias

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Top Questions

What is Signal?
Signal is a non-profit, private messaging app founded by Moxie Marlinspike. It allows users to exchange texts and voice messages, make calls, send photos and videos, and communicate in group chats via smartphone or desktop app. Every Signal conversation is protected with end-to-end encryption, so data is only viewable to chat participants.

Signal's "disappearing messages" feature lets users set a time period for how long their messages remain visible before deletion. Requiring a phone number has caused privacy concerns among some users. High-profile users include Edward Snowden, social justice organizers, journalists, and government officials. Unlike WhatsApp and most email providers, Signal can't supply user data to law enforcement, other than when the app was downloaded and last used.
1 Britannica Source
1. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What can you do with the Signal app?
With the Signal app, operated by the nonprofit Signal Foundation, you can exchange text and voice messages, make voice and video calls, and send photos and videos. You can also communicate in group chats using a smartphone or desktop app.

Every conversation on Signal is protected by end-to-end encryption, so data is only viewable to chat participants. With Signal’s disappearing messages feature, users can set a time period for how long their messages remain visible before they are deleted from the chat. Because Signal cannot view or audit messages, it has avoided some of the criticism faced by Telegram.
1 Britannica Source
1. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How does Signal help keep messages private?
Signal employs end-to-end encryption to ensure that only the participants in a chat can view the data. Every conversation on Signal is protected by this encryption method.

Additionally, Signal offers a "disappearing messages" feature, allowing users to set a time frame for how long messages remain visible before they are automatically deleted from the chat for all participants.

Unlike WhatsApp, which has faced criticism for sharing user data with Facebook, Signal is unable to provide user information to law enforcement, except for when the app was downloaded and last used. This strengthens its privacy stance compared to competitors like Telegram, where only specifically marked "secret" chats have end-to-end encryption.
1 Britannica Source
1. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What is end-to-end encryption in Signal?
Signal is a private messaging app that uses end-to-end encryption to secure all communications. This means that every conversation on Signal is protected, and data is viewable only to the participants in the chat. Unlike other messaging apps like Telegram, where only chats marked "secret" are encrypted, Signal applies end-to-end encryption to all chats by default. This ensures that no third party, including Signal itself, can view or audit the messages.
1 Britannica Source
1. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How is Signal different from other messaging apps like WhatsApp or Messenger?
Signal distinguishes itself from other messaging apps like WhatsApp and Messenger through its focus on privacy. Every conversation on Signal is protected with end-to-end encryption, ensuring that only the participants can view the data.

A key feature of Signal is the "disappearing messages" option, which allows users to set a time frame for messages to remain visible before they are deleted from the chat for all participants. While WhatsApp also uses end-to-end encryption, it has faced scrutiny for sharing user data with its parent company, Meta, for targeted advertising. Unlike Telegram, where only chats marked "secret" have end-to-end encryption, Signal applies it to all communications.
2 Britannica Sources
1. WhatsApp
2. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Who created Signal, and why do some people choose it for their communications?
Moxie Marlinspike (pseudonym for Matthew Rosenfeld) created Signal. He served as CEO of the Signal Foundation, a nonprofit organization, from 2015 to 2022.

Signal employs end-to-end encryption, ensuring only participants can view data. Its "disappearing messages" feature lets users set time limits for message visibility, enhancing privacy. Edward Snowden and others use Signal because of these features. Social justice organizers, journalists, and government officials also use it for secure communication.
1 Britannica Source
1. Signal
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Signal, private messaging app operated by the nonprofit organization Signal Foundation, based in San Francisco. Signal users can exchange text and voice messages, hold voice and video calls, send photos and videos, and communicate in group chats. The service can be accessed via a smartphone or desktop app.

Signal was created by cryptographer and entrepreneur Moxie Marlinspike (a pseudonym for Matthew Rosenfeld), who also served as the company’s CEO from 2015 to 2022. In 2010 Marlinspike and roboticist Stuart Anderson, founded the security start-up Whisper Systems, which released the private text and call services TextSecure and RedPhone.

The duo sold Whisper Systems to Twitter (now X) in 2011, but Marlinspike continued to build on their existing work. In 2013 he founded the open-source nonprofit Open Whisper Systems, which in 2014 released the initial version of Signal, which supported only phone calls. The following year, Signal added texting to the app. In 2018 Brian Acton, who had cofounded the messaging app WhatsApp but had left the company in 2017, provided $50 million to create the nonprofit Signal Foundation with Marlinspike. Signal Messenger LLC operates as the foundation’s subsidiary and was created at the same time. When Marlinspike stepped down as CEO of Signal Messenger in 2022, Acton was named interim CEO. In June 2023 Signal announced on X that Acton would stay on as Signal Messenger’s CEO.

Signal is a competitor of Acton’s former project, WhatsApp, which Facebook acquired in 2014. WhatsApp faced criticism for sharing user data with Facebook, which Facebook would then use to create targeted ads. Though WhatsApp now uses end-to-end encryption, its practices continue to be scrutinized by privacy advocates. On Signal, every conversation is protected by end-to-end encryption, with data being viewable only to chat participants.

Signal’s “disappearing messages” feature allows users to set a time period for how long their messages remain visible before they are deleted from the chat. The feature affects all participants in a chat, unlike deleting a message, which affects only one party. Signal requires users to enter a phone number to use the app and can alert users when numbers from their phone’s contacts join Signal. Both features have caused privacy concerns among some users.

One prominent Signal user is intelligence contractor and whistleblower Edward Snowden, who in 2013 leaked information regarding the surveillance of private American citizens by the National Security Agency (NSA). A personal friend of Marlinspike, Snowden once posted on X that he “use[s] Signal every day.” Signal is also used by social justice organizers in the United States and Hong Kong, as well as by journalists, intelligence professionals, and government officials, including members of U.S. Pres. Donald Trump’s administration. This has also led to scrutiny, as government officials are required by law to keep records of their communications.

Signal’s disruption of traditional technological surveillance methods can prove frustrating for government and law enforcement officials. When requested, WhatsApp and most email providers may supply user data to law enforcement. Signal is unable to provide any user information other than when the app was downloaded and when it was last used. Such features differentiate Signal from fellow WhatsApp competitor Telegram, in which only chats specifically marked “secret” are protected by end-to-end encryption. Signal cannot view or audit any messages, and it has escaped some of the scrutiny faced by Telegram, which critics say facilitates communication among neo-Nazis and other extremists. Signal enables communication between users and their contacts, whereas Telegram allows users to join groups of like-minded strangers. Telegram’s platform advertises such groups and lets users search for them with hashtags.

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