Reprinted from TidBITS by permission; reuse governed by Creative Commons license BY-NC-ND 3.0. TidBITS has offered years of thoughtful commentary on Apple and Internet topics. For free email subscriptions and access to the entire TidBITS archive, visit http://www.tidbits.com/ You Know What an Email Address Is, Right? Adam Engst Developer Samwho has built a [1]21-question quiz that tests your knowledge of what is and is not allowed in an email address. It starts easy but gets hard fast. Familiarity with [2]RFC 822, [3]RFC 2822, [4]RFC 5322, and [5]RFC 6532 is useful, but you'll still be surprised by some of the answers, such as ð@ð. References Visible links 1. https://e-mail.wtf/ 2. https://www.rfc-editor.org/rfc/rfc822 3. https://www.rfc-editor.org/rfc/rfc2822 4. https://www.rfc-editor.org/rfc/rfc5322 5. https://www.rfc-editor.org/rfc/rfc6532 Hidden links: 6. https://e-mail.wtf/ .