Have you moved your web pages, or simply deleted some old pages?

If so, chances are that those old pages are still indexed by the search engines (at least for a while) and so still hold value in terms of user experience and link equity.

So, rather than have a 404 error (link not found) page sitting there, add a 301 (permanent) redirect from these old pages to your new pages of similar content and the visitirs and page link values will be passed to the new page (and site).

This can easily be done through most hosting control panel’s (e.g cPanel) without the need for technical expertise.