Tim Berners-Lee, 1991
<window> ∟ <document> ∟ <head> ∟ <script> ∟ <body> ∟ <div> ∟ <form> ∟ <image>
1. Close every tag with an angle bracket ("End angle")
<div>
2. Close start tags with a bookend tag with a slash ("End tag")
<div>Welcome to my page!</div>
World Wide Web (W3) Consortium, 1996
Brendan Eich, 1995
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