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What the hell is <!DOCTYPE html>?

Amandeep Singh Malhotra on June 29, 2022

&lt;!DOCTYPE html&gt; &lt;!-- What the hell is this?? --&gt;&gt; &lt;html lang="en"&gt; &lt;head&gt; &lt;title&gt;Document&lt;/title&gt; &lt;/...
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Thomas Bnt ☕

Cool post about DOCTYPE! 👍🏼

Don't hesitate to put colors on your codeblock like this example for have to have a better understanding of your code 😎

console.log('Hello world!');
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Example of how to add colors and syntax in codeblocks

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Amandeep Singh Malhotra

Hey Thomas, since was my first post at dev.to, I was not aware of this. Thanks for your input. :)

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Thomas Bnt ☕

Oh don't worry! Very nice first post! And welcome to DEV! 👋🏼🚀

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Albert Sanchez • Edited
console.log('hi'); 
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Peter Vivo

I take look my old cv (around 2008) doctype and that was:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0//EN" "http://www.w3.org/TR/REC-html40/strict.dtd">
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When debugged :

console.dir(document.doctype)

{
  publicId: "-//W3C//DTD HTML 4.0//EN"
  systemId: "http://www.w3.org/TR/REC-html40/strict.dtd"
...restOfDoctype
}
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Saddly my old flash animation and program does not run in modern browser, I lost them, just keep the doctype.

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Randell Brian Knight

Very nice article about DOCTYPE! 🎉 It's good to have some useful background information about these topics. Thank you, Amandeep 😎

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Amandeep Singh Malhotra

Thank you 🙂

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Kunal Keshan

Awesome! didn't know about the quirks mode fallback if the DocType is not mentioned.

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CraftyMiner1971

Thanks for the simple explanation of the DocType! I'm so glad that the W3C people simplified the DocType, cos i would not be able to remember all that fancy code that went into the former starting line for HTML files.

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Amandeep Singh Malhotra

Thank you for going through this article. I have written another article which explains the this keyword in javascript. If you'd like to explore it, please go through this link. Thanks! ✌️

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Bhagya

Interesting Article

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🚩 Atul Prajapati 🇮🇳

In starting days of my learning web development i have asked several times to my institute teacher but they are unable to solve my curiosity 😌 thanks for your priceless effort 🙏🙏 shatsriya a kal 🙏

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UponTheSky

Nice Investigation! It was really informative!

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Yongchang He

This is interesting!

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InvalidLenni

Thanks! I didn't know that, but now I know that! Nice post about <!DOCTYPE>

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Wj • Edited

Too detailed for 1 line of code 🤯. Good practice though especially when it comes to bigger stuff to discuss about.

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Andrew Baisden

Nicely done good explanation.

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Amandeep Singh Malhotra

Thank you 🙂

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imonem

I love history lessons, keep'em comin'

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Steven Barrios

This was a great post!

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Tomasz Jakut

Older HTML versions weren't actually based on SGML. That was just the theory but it wasn't done in practice. Otherwise it would require browsers to fetch all these .dtd files to parse HTML elements correctly – especially if someone came up with their own one. Parsing rules were more likely just hardcoded into the browsers and later just codified in HTML5 spec.

BTW DTD-based DOCTYPEs created one other issue: DDOS-ing W3C's servers ;)

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Calin Baenen • Edited

Does "Quirks Mode", ðe name, refer to ðe fact each browser handles þings differently?
I'd assume "yes", but it could mean someþing different.

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Ava Rogers

Thats HTML5

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Luiz Carneiro

Nice and simple! :) Enjoyed it!

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Tiago Rangel

Interesting!

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