There is difference between a 404 and a 410 when a page is navigated.
404 Document Not Found :- Its simply means that page has not been found. There may be a spelling mistake, the page may be temporarily missing or it may have been moved without being redirected. Spiders will come back and look for the page again, and it's been my experience that they'll re-include it in the index once it's found again.
410 Document Gone:-Its means that the page has been permanently removed.
404 errors are the HTTP response codes that every web developer will know and understand: Page not found. However, it may be interpreted by search engines as 'Page not found, but we'll check back some other time'. The 410 response is supposed to mean 'Page not found, permanently'; it's a web site's way of saying that the requested URL will never exist.
Whether search engines really bother to tell the difference between these two http statuses is unclear. For example, back in late 2011 Matt Cutts presented a webmaster video in which he 'will need to check with the crawl team' if they treat 404 and 410 errors differently. He's given no public response to that, as yet.
404 is a bit less then 410 :D