text/plain vs text/javascript

Question

I noticed that there's a whole bunch of different content types, some of them seem redundant.

Wouldn't a js file that's served as text/plain work just as well as if it was served with text/javasctipt?

I plan on making a page that's serve-able as a ajax/json/jsonp file (with or without a callback) or as a plain page that users on a dumb phone or with no js can view as a text file.

Is there any disadvantage as always displaying a page as text/plain ? Will it ever be a problem if I'm getting it as a script? What about the inverse?

• poncha: take a look here: stackoverflow.com/questions/4101394/javascript-mime-type , theres detailed explanation about javascript mime type

Answer 1

Wouldn't a js file that's served as text/plain work just as well as if it was served with text/javasctipt?

Only if it would be executed as JavaScript regardless. If text/plain meant something to the client distinct from text/javascript then the effects would (could) be different. Fortunately it usually doesn't when the browser loads it due to a <script> tag.

Answer 2

An advantage of using text/javascript is that it will allow you to include non '.js' postfixed files and they will be rendered as javascript.

For instance, I usually have a global.config file - which is a javascript written configuration object. I can use the postfix '.config' which is very helpful visually - but still use have it render as javascript.

• qwertymk: What do you mean "rendered as javascript" ?
• Blender: I think interpreted is a better word.
• qwertymk: @Blender: won't the js still run tho?
• Blender: If it's included in a <script> tag, sure.

Answer 3

When a Javascript is inserted dynamically, the navigator will give you correct events and states of reception (readyState with Intrenet Explorer, onload with FireFox) if the content is type "text/javascript". It can make wrong or lazy response if it's "text/plain".