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HTML

Posted by Andrew Booth
Andrew Booth
1,578 Points

Did you know that DOCTYPE is NOT case sensitive?

I just found out today and it's super interesting!

<!DOCTYPE html>

and

<!doctype html>

2 Answers

Steven Parker
Steven Parker
243,228 Points
Steven Parker
Steven Parker
243,228 Points

Actually, the complete official specification is:

8.1.1 The DOCTYPE

A DOCTYPE is a required preamble.

A DOCTYPE must consist of the following components, in this order:

  1. A string that is an ASCII case-insensitive match for the string "<!DOCTYPE".
  2. One or more ASCII whitespace.
  3. A string that is an ASCII case-insensitive match for the string "html".
  4. Optionally, a DOCTYPE legacy string.
  5. Zero or more ASCII whitespace.
  6. A U+003E GREATER-THAN SIGN character (>).

And tag names and attributes are also case-insensitive, but "best practice" is to use caps for DOCTYPE and lower-case for tag names and attributes.

Andrew Booth
Andrew Booth
1,578 Points

It was meant to be a fun facts thing......

I did not need the full official specification list.

Steven Parker
Steven Parker
243,228 Points
Steven Parker
Steven Parker
243,228 Points

I had fun looking up the specs. :smirk:
And I'd bet most folks didn't know about the tags and attributes being case insensitive, too.

Andrew Booth
Andrew Booth
1,578 Points
Andrew Booth
Andrew Booth
1,578 Points

What is your favorite programming language?

Steven Parker
Steven Parker
243,228 Points
Steven Parker
Steven Parker
243,228 Points

Tough call. I'm a long-time fan of C, but I recently learned GO (here) and think it's very cool.