A "Server Error" occurs when a web server encounters an issue that prevents it from fulfilling a request made by a user. This can happen for various reasons, such as misconfigurations, software bugs, or server overload. When a server error occurs, users typically see an error message, often with a code like 500 Internal Server Error, indicating that something went wrong on the server side. These errors can affect website functionality, making it impossible for users to access certain pages or services. Website administrators usually need to investigate the server logs and settings to identify and resolve the underlying problem. Regular maintenance and updates can help minimize the occurrence of server errors.