Here are the list of HTTP Hypertext Transfer Protocol Codes List like 200, 300, 400 and 500. Get to know the HTTP Status Codes for SEO and Search Engines.

1. SEO HTTP Response Codes List
First will know the abbreviation of HTTP, HTTP stands for Hypertext Transfer Protocol.
These HTTP codes are in 3 digit numeric number. Generally, HTTP is a TCP/IP based
communication protocol, it is used to deliver the HTML, Images and Query Result files
etc. on the World Wide Web.
These HTTP Response Codes are communicate between you and servers on the internet,
i.e browsers sends a request to a server for the information. These requests might be
images, videos, files and etc, this is called HTTP request. When a server receives that
request, it sends back an HTTP Response, with information for the You/Browsers.
Here are the common HTTP Response Codes are,
2xx: Success It means the action was successfully received, understood, and accepted.
3xx: Redirection It means further action must be taken in order to complete the request.
4xx: Client Error It means the request contains incorrect syntax or cannot be fulfilled.
5xx: Server Error It means the server failed to fulfill an apparently valid request.

3. HTTP Status Codes for SEO and Search Engines
200 OK
The request has succeeded. This is considered correct for most scenarios.
301 Moved Permanently
The requested resource has been assigned a new permanent URI and any future
references to this resource should use one of the returned URIs. The 301 redirect, as it is
commonly called by SEOs, should be utilized any time one URL needs to be redirected to
another.
302 Found
A status code of 302 tells a client that the resource they asked for has temporarily moved
to a new location. The response should also include this location. It tells the client that it
should carry on using the same URL to access this resource.
403 - Forbidden
A 403 status code indicates that the client cannot access the requested resource. That
might mean that the wrong username and password were sent in the request, or that the
permissions on the server do not allow what was being asked.
404 File Not Found
The best known of them all, the 404 status code indicates that the requested resource was
not found at the URL given, and the server has no idea how long for.
410 - Gone
A 410 status code is the 404's lesser known cousin. It indicates that a resource has
permanently gone (a 404 status code gives no indication if a resource has gine
permanently or temporarily), and no new address is known for it.
500 Server Error
Server Error: Valid request was made by the client, but the server failed to complete the
request.
503 - Service Unavailable
A 503 status code is most often seen on extremely busy servers, and it indicates that the
server was unable to complete the request due to a server overload.

4. External Sources:
https://moz.com/learn/seo/http-status-codes
https://www.addedbytes.com/articles/for-beginners/http-status-codes/
http://www.tutorialspoint.com/http/http_status_codes.htm