Why do browsers need vendor prefixes for CSS3? What is stopping them from just using the standard CSS3 properties? [duplicate]

Question

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Why do browsers create vendor prefixes for CSS properties?

For example, if I have an image that I'd like to rotate, why does Google Chrome do nothing when I use transform: rotate(50deg); but work fine when I use -webkit-transform: rotate(50deg);?

Isn't the whole point of having the standard to make it so that a programmer/designer only writes the same code once, and not once for each of the browsers? Is this something that is going to be changed in the foreseeable future or will it always be this way? I'm only just starting to use CSS3 and this seems really bizarre to me.

Answer 1

CSS3 has not been formally adopted as a complete standard yet—it is still a draft proposal.

Vendor specific tags allow the vendors to begin to implement CSS3 draft standards or proposed ideas for CSS3 now using experimental implementations, while ensuring that their current rendering with these proprietary tags can be distinguished in the future from their rendering of the actual CSS3 tag as per the final spec, even if that is different.