A 5xx error is a type of HTTP status code indicating that a web server has encountered an error and cannot fulfill a user's request. These errors are generated when the problem lies with the server itself, not the user's device or internet connection. Common 5xx errors include 500 (Internal Server Error), 502 (Bad Gateway), 503 (Service Unavailable), and 504 (Gateway Timeout). Such errors can be temporary or signal deeper technical issues on the server side. For users, a 5xx error means the website is temporarily inaccessible, and for website owners, it signals the need to investigate server performance or configuration problems.