A 301 redirect is an HTML protocol that automatically directs the user or search engine to an alternate domain. You can think of this like using a forwarding address when you move.
The 301 protocol is a permanent redirect as opposed to a 302 redirect, which is temporary. A 302 redirect would normally be used when you’re changing or updating your website. A permanent 301 redirect is best used when you change the domain name or choose to amalgamate several domains under a single domain name.
Why Use a 301 Redirect
As your business grows, you may want to change your domain name. When this happens, you don’t want to lose customers that have been using your existing URL, nor do you want to lose your current search engine ranking. This is where you’ll make use of a 301 redirect. Let’s say you started out with the domain http://mysite.com and you change it to http://mynewsite.com. In order to maintain inbound links to the original site, you’ll need to link it to the new site using a 301 redirect.
Another example would be if you started with a site to sell corporate gifts and called it joescorporategifts.com. Later, you expand into corporate apparel and register the new domain, joescorporateapparel.com, and then a third site, joescorporatecommunications.com. As your business grew, you created new domains to sell new products and services. A time may come when you want to combine these services under one umbrella. To do this, you create a new domain, joescorporateservices.com. When you launch the new site, you’ll link all three of your previous sites to the new domain. You may choose to direct each of the original sites to a certain page on the new site. For example, if a user or search engine is directed to the joescorperategifts.com site, they will be redirected to joescorporateservices.com/corporategifts. This means that all links and search engine results that direct users to the original site will be redirected to the page on the new site that relates to that topic.
It’s important to remember that internal links on your site must be changed to match the redirected URL.