There are times when you are browsing the Internet where you may get some cryptic messages rather than the page you were expecting. Chances are you are receiving a page from the web server where the site is hosted that details an error message that was encountered.
These errors help tell what is going on and why the user is experiencing problems. You may also hear these referred to as browser error messages or Internet error codes.
The code is typically just the number. But, a full message is comprised of the code and the reason phrase. These two components combine to make the HTTP Status Line. For example, the 404 Not Found error you see is the HTTP Status Line. 404 is the code and Not Found is the reason phrase.
The main groups of error messages we will deal with in this article are the 400 level error codes and the 500 level error codes. The make up a majority of the issues you will see when browsing the Internet.
400 Level – Client Errors
The 400 level of client error codes are typically a result of something that occurred on the client side of the equation. For example, typing the wrong address into the search bar, or using incorrect characters can result in a client error to occur. If you type in a an address in a bar that doesn’t exist then the server on the other end will let you know that the page is not found. This is usually the case if you mistype an address or incorrectly format a url
The most common client error codes are 404 Not Found, 403 Forbidden and 400 Bad Request.
500 Level – Server Errors
These errors occur when the client does everything correctly, but there is an issue on the server side that makes it unable to fulfill the request. These types of errors will need to be corrected by the server administrator, and are no fault of the website visitor or browser.
The most common of these error codes include the 500 Internal Server Error, 503 Service Unavailable and 502 Bad Gateway Error.
There are also errors at the 100, 200 and 300 level. These are typically more informational. Furthermore, there are more 400 and 500 level errors as well. However, the ones we mentioned are the most common.
Be sure to check back to this article as we will be writing more detailed posts on individual errors and including links from this article to them. We will also work to write a post with a list of these errors for easy reference.