I am trying to get browser compatibility built in on a website I am developing, and from what I have found out you use X-UA-Compatible to determine this. However what I cannot figure out is how I set the code. I need compatibility for IE 9+, for latest Chrome, and for latest Firefox.
I have seen meta tag such as <meta http-equiv="X-UA-Compatible" content="chrome=1"> but how do I create this for the above 3 browsers, and is there also any other code I need to include on the webpage. If there is any useful for explaining this meta tag, please include them.
I think you're confused about what X-UA does. It does NOT ensure your site is compatible in all browsers. It simply forces IE to behave a certain way. The following example forces IE to use IE9 rendering mode if possible.
<meta http-equiv="X-UA-Compatible" content="IE=9">
But what if your site visitor doesn't have IE9? Then what? A fallback would be this which says, use IE7 or IE9 but not IE8 mode:
<meta http-equiv="X-UA-Compatible" content="IE=7, IE=9">
The bigger issue is if your site isn't performing well in all major browsers, chances are something's wrong with it. Validate your code, fix errors & re-examine your design approach.
HTML - http://validator.w3.org/