This error typically occurs when a user tries to access a webpage that no longer exists or has been moved without a proper redirect. When a browser requests a URL, the server checks for the resource; if it cannot locate it, it responds with a 404 status, often accompanied by a message indicating that the page is not found. This is a common issue on the web and can arise from various reasons, such as broken links, mistyped URLs, or outdated bookmarks.
404 Error Example
For example, if a user types in a URL for a product that has been removed from an e-commerce site, they may see a 404 Error page informing them that the requested page cannot be found.