The White Screen of Death occurs when a PHP fatal error or database connection issue terminates script execution. WordPress hides these errors from the public by default to maintain security. This results in the browser rendering a blank screen because the server provides no output or headers before stopping.
Memory exhaustion or incompatible code typically triggers this state. You often see this after installing a new plugin or updating core files. It signals a critical failure where the application can no longer function without manual intervention in your server files.