301 redirect
What is 301 redirect ?
301 redirect implies permanently redirecting the pages that are old to new. The URL of such a website may have taken a new format, whereas the old web page may have a 404 error. As an HTTP status code, it directs all future requests to the new URL, which can successfully help in moving into the newest location.
Other than permanently removing or deletion of web pages, 301 redirects are helpful when migrating to a new domain, organise the site structure, moving from non-www to www URLs, enabling HTTPS for the site, merging domains more than two, and so on.
This type of redirect doesn’t necessarily lead to an old page showing a 404 error; the users will be redirected to a new page where they don’t need to do it manually, and they may not know that the old URL has changed.