HTTP Response Status Codes
HTTP response status codes are issued by web servers in response to a client request.
Three digits long - HTTP status codes should tell us what type of response a server is issuing.
For example if a server responds with a 200 HTTP response status code, this means that the page or resource loaded successfully.
Types of HTTP Response
There are 5 general classes or categories of HTTP response status codes, with the first digit indicating which type a particular response is.
1xx Informational response
1xx responses mean that the server has received the response and is processing the request.
2xx responses are provided when the server has received, understood and then successfully provided the requested resource.
4xx Client Error
4xx responses are provided when a client has erred, such as by requesting a resource that is not available at that location. The most common type of 4xx error is a 404 Not Found.
5xx Server Error
5xx responses are provided when a server has been unable to fulfil a request due to a server-side error.