Definition
A 404 Error (also known as "404 Not Found") is an HTTP status code indicating that the requested webpage or resource could not be found on the server. This typically occurs when a URL is broken, the page has been deleted, or the user mistyped the web address.
Why It Matters
404 Errors can negatively impact user experience, website credibility, and SEO performance. When visitors encounter a 404 page, they may leave the site, increasing bounce rates and reducing engagement. Additionally, search engines like Google may lower the rankings of sites with excessive 404 errors, as they signal poor site maintenance.
Key Components
- HTTP Status Code: A 404 is a client-side error, meaning the request was made correctly, but the resource isn't available.
- Page Not Found Message: Websites typically display a standard or custom message informing users that the requested page is unavailable.
- Redirects (or Lack Thereof): A 404 page may provide navigation options, a search bar, or links to other pages to keep visitors engaged.
- Server Response Headers: When a page is missing, the server sends a 404 status in the HTTP response header.
Best Practices
- Create a Custom 404 Page: Include helpful navigation links, a search bar, and a friendly message to guide users.
- Implement Redirects: Use 301 redirects for permanently moved pages to maintain SEO value.
- Monitor and Fix Broken Links: Regularly check for and repair broken links using tools like Google Search Console or Screaming Frog.
- Optimize for SEO: Use proper server configurations to ensure search engines understand which pages are removed permanently and which are temporarily unavailable.
Real-World Example
Imagine an online retailer moves a product page to a new URL but fails to redirect the old link. A customer who clicks an outdated link from a search engine lands on a 404 page instead of the intended product. Frustrated, they leave the site and purchase from a competitor. By setting up a 301 redirect, the retailer could have guided the customer to the correct page, preserving both the sale and user experience.