Changing the address (URL) of live web pages is often a really bad idea. The result is that all search and referral traffic suddenly goes nowhere, i.e. to a 404 page.
Moreover, links to your existing pages may be valuable to your Google rankings, but when the page is gone, so is essentially this 'vote' as perceived by the algorithm.
Unfortunately, situations will arise when you really do need to update your URLs, such as when migrating to a new domain or cleaning up the site structure for other reasons.
There are also valid reasons for removing pages entirely, e.g. obsolete products, but these should generally be handled in much the same way.
What's a 301 Redirect?
The 301 designation is an HTTP status code just like the more familiar '404 – Not Found'. But instead of telling users (and bots) that the content is missing, a 301 tells them that it has been moved to another, specific URL. It might look something like this in the server configuration file:
301 /old-page /new-page
The 301 status code also says that the move is permanent, whereas 302, for example, means that the redirect is temporary.
301 Redirects Using a WordPress Plugin
If you are using self-hosted WordPress, the good news is that you don't need to be versed in web server functionality to redirect your pages without running afoul of users or Googlebot.
Via the WordPress plugin directory, you have access to a wide range of free plugins that manage 301 redirects directly in the Admin interface.
Redirection: A Free and Versatile Option
My personal favorite plugin by a wide marigin for managing redirections (and a few other things) is one appropriately named 'Redirection'. It has no paid upgrades, but still offers plenty of useful extras.
After installing and activating the plugin, you will find it under Tools --> Redirection.
Adding your own 301 redirects here is no more difficult than inserting the page's existing address (Source URL) and the page's new address (Target URL) and clicking Add Redirect.
Just remember that the URLs must be relative, i.e. start with the first forward slash (so simply /page-to-move instead of https://www.fulltextmedia.se/page-to-move). If you haven't already done so, you also need to remove the original page for the redirection to work.
URL and 404 Monitoring
The Redirection plugin also features the same type of built-in URL monitoring offered as a paid add-on in the popular Yoast SEO plugin. This means that pages are automatically redirected when you change the URL.
Yet another useful feature is 404 tracking. The extension can be set during installation (or later) to log all 404 errors so you can easily set redirects to the new address.
Most likely you don't need to create 301 redirects for everything that shows up on this list, but it's an easy way to spot obvious issues. It is also possible to sort the list by user agent, e.g. Googlebot.
In addition, the Redirection plugin has a range of more advanced configuration options, including import/export in any format and the ability to save the changes to the server's htaccess file.
All in all, It's a very impressive feature set for this entirely free plugin.
