Be careful with .data(), it will also convert strings to numbers it shouldn't/can't convert, and silently fail. If you put a 64-bit integer in a data html-attribute, jQuery will see it as a number (and thus cast it to a number), although Javascript doesn't support 64-bit integers. The result will be a completely different number, without any warning.
An example: If you have a twitter uid, save it in a data-twitter-uid-attribute and fetch that with jQuery.data('twitter-uid'), you'll get a faulty result, because a twitter uid exceeds Javascript's integer size limit.
Comment
Be careful with .data(), it will also convert strings to numbers it shouldn't/can't convert, and silently fail.
If you put a 64-bit integer in a data html-attribute, jQuery will see it as a number (and thus cast it to a number), although Javascript doesn't support 64-bit integers. The result will be a completely different number, without any warning.
An example: If you have a twitter uid, save it in a data-twitter-uid-attribute and fetch that with jQuery.data('twitter-uid'), you'll get a faulty result, because a twitter uid exceeds Javascript's integer size limit.