What is the difference between domain aliases and 301 redirect?

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Domain Aliases allows you to assign more than one domain name to one web site with Action you can have an unlimited number of domains pointing to a single web site.

For example, if you have the domain "mydomain.com" set up as an alias to the hosting account for "myotherdomain.com," anyone browsing to "mydomain.com" will go to the "myotherdomain.com" Web site.

With 301 redirect, the Web browser connects to one Web server hosting "mydomain.com", and that Web page redirects the browser to another server hosting "myotherdomain.com".