While it probably isn’t terribly important to the average web user or business person to be highly knowledgeable about these codes you’ve likely come across them in your travels on the Net so you might still want to know what they are.

Most web servers adhere to a standardized set of result codes that every request/response falls under. Each series has a general meaning and within the series there are very specific result codes.

• 200 – Success
  Everything is working properly. (these are generally silent or not sent to the browser because if everything is working ok you want to look at a web page not a message that says everything is ok)
• 300 – Redirection
  You are being sent from one page or url to another. (these are often silent because you are generally sent to a new location which should respond successfully)
• 400 – Incomplete
  Something happened and the request didn’t complete successfully. (these are generally sent to the browser in some way)
• 500 – Error
  There was an internal server error either related to the server or the software running on it. (these are almost always sent to the browser)

I’ll pick out a few of the more popular response codes you might have seen and provide some info about them, but here is a good list of all the possible response codes if you want the gory detail.

• 301 – The page you were trying to get to has moved to a new location. The server should automatically redirect you to the new page and you shouldn’t have to do anything further. Search engine marketers use 301’s a lot when a page is removed or a new website is created so that visitors and search engines can find the new page easily.
• 403 – You are not authorized to view this page. Either you authenticated incorrectly or your IP address is restricted from viewing the page. In either case its back to the drawing board for you.
• 404 – The page you were trying to get to does not exist. It might have existed in the past and has been removed or the link you followed was just wrong. There is no redirect and you’ll have to find your page another way. Our creative team put together a great 404 page for our site that hopefully not many people get to see. Check out http://www.atlanticbt.com/404
• 500 – Any 500 code probably means that something out of your hands has gone wrong. You might try back in a few minutes in case it’s a server load issue but if the issue doesn’t clear up you might try and let the manager of the website know that you had an issue. Try to remember what you did prior to the error because that can be helpful for troubleshooting.