- Server borked? 503.
- Access denied? 403.
- Not found? 404.
- All good? 200.
Up until now there hasn't really been a concise, easy to follow, way of figuring out what response code is the most appropriate. Allan Dean fixes that with his handy dandy activity guide for determining the appropriate HTTP response. Nice to see it also covers ETags.
It's kind of fun - now you can play the "find the 201" game.
Should be very useful for RESTful developers.