How does the browser knows how to interpret the script tag?

Question

According to this:

http://www.w3.org/TR/1999/REC-html401-19991224/interact/scripts.html

The type of script my be added in the script tag. Some values are: "text/tcl", "text/javascript", "text/vbscript".

Recently I've seen in this page: Cofeescript in 1,2,3 the following:

 <script src="coffee-script.js"></script>
 <script type="text/coffeescript">
         alert "Hello CoffeeScript!"
 </script>

And works great! ( I had to download the cofeescript library and use the one in the extra folder )

My question is. How does the browser knows that a given script should be handled? I have no idea.

@Oscar :-) Voted to delete? Can't you delete the question and start a new one? — Shoban, Feb 23 '11 at 23:21
hehe I've found the reason. The <script> tag breaks SO markdown http://meta.stackexchange.com/questions/80431/using-htmls-script-tag-breaks-so-serverside-markdown-somehow — OscarRyz, Feb 24 '11 at 00:11
Some good information in the answers to this question: http://stackoverflow.com/questions/2706290/why-write-script-type-text-javascript-when-the-mime-type-is-set-by-the-server/2706617 — Alohci, Feb 24 '11 at 01:01

score 1 · Answer 1 · edited May 23 '17 at 11:55

Seeing as you can't finish your answer, it's not yet entirely clear what your question is ;)

But the answer to this question is related: The type attribute of SCRIPT and STYLE elements in HTML?

Summary:

type is indeed a required attribute in HTML 4
it defaults to text/javascript in HTML 5

as far as I know, text/javascript is the de facto default in all modern browsers if the property is missing even in HTML 4.

score 1 · Answer 2 · answered Feb 23 '11 at 23:21

1

Since HTML5, the type attribute is optional (it is required in HTML4 though) and the default value is text/javascript.

answered Feb 23 '11 at 23:21

Harmen

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score 0 · Answer 3 · answered Feb 23 '11 at 23:20

0

The browser simply recognises some specific types of script, and ignores everything else.

Internet Explorer for example recognises the type "text/javascript" and runs the script, eventhough it actually runs it as JScript.

answered Feb 23 '11 at 23:20

Guffa

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score 0 · Answer 4 · answered Feb 23 '11 at 23:21

I believe that the default in browsers is to interpret a script tag as holding JavaScript; whilst the spec that you've listed indicates that there is no default value for the type attribute, that doesn't mean that browsers won't provide their own default.

How does the browser knows how to interpret the script tag?

4 Answers4