The 200 class of HTTP response status codes is a general-purpose response returned by a server to indicate that a client’s request was successfully received, understood, and accepted. A 200 OK response indicates that the server has successfully located the resource and is sending it to the client. This is by far the most ubiquitous and desired response code for web requests. When a user navigates their way to a page, the browser sends a request to the server. When the server finds the page requested and successfully serves it, it gives a response of 200 OK. The user typically does not see the status code unless he is viewing the network traffic. However, its function is crucial in client-server communication. 200 response codes are deemed essential for a website’s normal function and SEO. Search engines rely on 200 codes for crawling and indexing web pages. All other codes, like 404 Not Found or 500 Internal Server Error, imply problems with requests or the server itself, which adversely affect the user experience and SEO.