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That was the contents of the first email ever sent, back in 1971.1 It's not the most earth shattering of emails, but that first humble email started a technology that eventually transformed communication across all sectors of society.
By the 1980s, the email protocol was standardized and included features like replying, forwarding, CCing, and BCCing.2
Companies soon realized the consumer appeal of email and developed easy-to-use webmail clients, like Hotmail in 1996, Yahoo Mail in 1997, and Gmail in 2004.3
The original Gmail interface in 2004. Image source: David Wang, Flickr
Decades later, email is still incredibly popular: 430 billion emails were sent every day in May 2019. 4

Email spam

Unfortunately, the biggest use of email is the one that email recipients don't want: spam! One research group estimates that as much as 85% of all email is spam. 5
Sometimes spam mail is just advertising for products that we don't want—the junk mail of the Internet—but often times spam mail is more sinister, containing phishing attempts and malware attachments. An unaware email user might accidentally reveal their private information or infect their machine, simply by reacting to an email.
Emails from my spam folder, both from marketers and scammers.

Email privacy

When one person sends an email to another person over a secure connection and a safe access point, the parties that can access the email contents are the sender, recipient, and the organizations that administer the email servers.
If either of the email web servers are attacked or if someone in the email organizations goes rogue, then a user's emails may become exposed to the world. Fortunately, for privacy-concerned users such as journalists or politicians, there exist email services that will fully encrypt the emails on their servers. If the email administrators can't read the emails, then an attacker can't, either.
There is a much more common way that emails get shared beyond the sender's original intended audience: forwarding, CC'ing, and BCC'ing. A recipient does not need a sender's permission to share an email more widely in those ways. We can request that a recipient does not share an email, but they may not always remember our wishes or respect our privacy.
My brother thwarting my attempt at a secret email.
In 2012, the US Department for Homeland Security discovered that a Customs & Border Patrol officer had been auto-forwarding all their emails to a personal Gmail account. Even worse, the officer had mistyped their address and was accidentally forwarding to a civilian with a similar name. 6
Some email clients have added a "confidential" mode to disable forwarding of confidential messages, but it only works between two users of the same email client (such as Gmail ↔ Gmail) since it is not a part of the email protocol itself.
Email can be one of the most private forms of communication on the Internet, but users need to consider the risks of data breaches, unauthorized access to their Internet connection, and accidental or intentional email sharing.
🙋🏽🙋🏻‍♀️🙋🏿‍♂️Do you have any questions about this topic? We'd love to answer—just ask in the questions area below!

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