Hypertext Transfer Protocol (HTTP) is a primary mechanism that distributes files (text, sound & etc.) on the World Wide Web. HTTP status code is three-digit codes that indicate the response and status of HTTP requests. Hypertext Transfer Protocol Status Code is important to know if, you want your website to continuously rank higher in search engine result pages.
Major types of HTTP Status Code
Status Code 100 (1xx Informational)
Status Code 200 (2xx Success)
Status Code 300 (3xx Redirection)
Status Code 400 (4xx Client Error)
Status Code 500 (5xx Server Error)
Important Status Codes for SEO
200 OK: - 200 OK status code is a standard response for succeeded of the request. This is a perfect status code that you should expect to see for every web page because OK status implies that you can be indexed & gain traffic.
301 Redirection: - HTTP Status Code 301 recommended only when the need occurs for Permanent Redirection of old pages to the new location. It is preferred status code by SEOs to redirect content on a website.
302 Found: - It is also known as a temporary redirect. From the user's point of view, it is same as 301 redirections, because they visit one page but redirect to another.
But there is a big difference between 301 and 302 Redirection - 301 is temporary web forwarding while 302 is permanent web forwarding. In 302 redirection Google does not pass any link value to the new URL, they consider it only temporary.
404 Not Found: - It is a status code that everyone knows. The requested file or resource does not exist on the server at this moment. This should occur when the server cannot find any matching page on the server. Often webmasters use "404 Error" text to display on the page and the response Code is 200.
401 Gone: - 401 errors mean Gone. It tells the users that the requests file no longer available. In search engine terms, the server returns the 401 response only when the requested resource is permanently expired.
503 Service Unavailable: - This Status Code tells the users that the service or file that requested is temporarily unavailable. 503 should be used when the server was down for a short period of time that ensures the search engine to come back after the short time.
500 Sever Error: - It is a general error that is not linked by user as well as developer too because it indicates that something has gone wrong on-site server but could not recognize what the exact issue is.