"An important milestone for the WhatsApp community. Now all your conversations and calls are encrypted to keep you and your information safe when you use the latest version," said Facebook CEO Mark Zuckerberg said in a statement on Wednesday.

Facebook acquired California-based WhatsApp in 2014.A full end-to-end encryption means that over one billion users of WhatsApp, when running the latest version of the messaging app, every call they make, and every message, photo, video, file, and voice message they send, will be end-to-end encrypted by default, and can only be deciphered by the intended recipient.

"The idea is simple: when you send a message, the only person who can read it is the person or group chat that you send that message to. No one can see inside that message. Not cybercriminals. Not hackers.

Not oppressive regimes. Not even us," said Jan Koum, CEO and co-founder of Whatsapp in a blog post on Tuesday. Encryption is one of the most important tools governments, companies, and individuals have to promote safety and security in the new digital age. Recently there has been a lot of discussion about encrypted services and the work of law enforcement, Koum added.

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