Is it safe to use code from code.jquery.com for long-term application?

Question

I am using Ajax / jquery on a webpage i am designing... in order for it to function, i include (at the top of my page) the javascript at: http://code.jquery.com/jquery-1.4.4.js

This works great and all, but i have a fear that 1) the code might get changed without me knowing, then i encounter problems and try to debug for days / hours before finding that the code at this site changed

2) the website is no longer used / specific code no longer hosted years from now

So would it be safer to save that javascript file onto my server, and access it from there?

Answer 1

You should use either a Microsoft or Google CDN. It will be much faster, it will be cached for a lot of your users and it's guaranteed to be there, as opposed to the jQuery link you include.

Answer 2

http://code.jquery.com is jQuery's CDN (provided by Media Temple). The code at http://code.jquery.com/jquery-1.4.4.js will never change; jQuery will release a new version (which will be at a different URL), if anything needs to change (which happens all the time; version 1.5b was released today).

The jQuery guys know what they're doing, and they setup a CDN so people can easily link to jQuery. They're just as (un)likely to bring down the CDN as Google and Microsoft are at bringing theirs down.

See http://docs.jquery.com/Downloading_jQuery for more information.

Having said that, it would seem the Google hosted version (http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js), is referenced more in websites; this leads to a small performance advantage as far as your users are concerned, as the file has more chance of being cached.