Facebook-owned WhatsApp has updated with end-to-end encryption.

The latest version of the messaging client now ensures all messages, photos, video, files, and calls are completely secure for its 1 billion users (no matter whether they are using iPhones, Android, Windows, Blackberry, or Nokia phones). That means only the sender and receiver of any given message will be able to see the contents of said message. Even WhatsApp won't have access to the message's contents.

End-to-end encryption will not change how you regularly use WhatsApp, but it will make it harder for WhatsApp to allow law enforcement, governments, and other authorities access to your private communications, even if they have a warrant. Theoretically, WhatsApp is now one of the most secure ways to electronically converse with people across the world and various platforms.

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End-to-end encryption is basically a secure method of communication. WhatsApp's rollout of end-to-end encryption prevents cyber-criminals, hackers, telecoms, and even governments from accessing the messages you've sent to other WhatsApp users. The idea behind end-to-end encryption is that your messages, media, and calls are now secured from falling into the wrong hands.

Here's how WhatsApp has explained the new security measure it offers:

"Many messaging apps only encrypt messages between you and them, but WhatsApp's end-to-end encryption ensures only you and the person you're communicating with can read what is sent, and nobody in between, not even WhatsApp. This is because your messages are secured with a lock, and only the recipient and you have the special key needed to unlock and read them. For added protection, every message you send has its own unique lock and key."

WhatsApp has been encrypting text messages since 2014 and spent two years teaming up with nonprofit software group Open Whisper Systems in order to offer end-to-end encryption across the service. This rollout comes in the wake of Apple's refusal to make a backdoor for an iPhone 5C (all of Apple's devices are end-to-end encrypted) owned by one of the San Bernadino shooters.

Jan Koum, the CEO and co-founder of WhatsApp, said in a blog post that he believes people deserve security and the confidence to speak their minds about sensitive information. It is therefore doing what it can to keep "people's information out of the hands of hackers and cyber-criminals." He also said that he personally believes people's private communication should be protected:

"The desire to protect people's private communication is one of the core beliefs we have at WhatsApp, and for me, it's personal. I grew up in the USSR during communist rule and the fact that people couldn't speak freely is one of the reasons my family moved to the United States."

Keep in mind WhatsApp is now unable to hand over messaging data, even if authorities are demanding access, but despite the strength of the encryption, it is not impossible for others to gain access.

WhatsApp end-to-end encryption - which, as of 5 April, the integration is fully complete - works for chats, group chats, attachments, voice notes, and voice calls across Android, iPhone, Windows Phone, Nokia S40, Nokia S60, Blackberry, and BB10.

End-to-end encryption on WhatsApp is enabled automatically. There is no need to turn on settings to secure your messages. WhatsApp said it will notify users of the encryption status for chats, including showing a notice in the messaging screen, during this beginning roll-out phase.

WhatsApp users can confirm the person they are chatting with is legit (rather than a hacker or someone intercepting your messages) by verifying the authenticity of the encryption session via scanning a QR code or reading aloud a number string. You can read more about that from here.

Check out WhatsApp's blog or Open Whisper Systems' blog for more details.