What is a 301 Redirect.

A 301 Redirection is the permanent relocation of a url page/domain to a new location.

W3C Status Code Defintion

Redirecting urls and domains are a critical part of not only general web maintenance but also any SEO campaign.

You will often find it referred to in different guises, domain redirection, 301's, domain / web page forwarding.  In essence they all mean the same thing putting something somewhere new and signposting the way to get there.

Most modern CMS's handle redirection quite well but frequently limit the functionality to basic redirection so you can use clean urls, however this is rarely good enough for any serious seo.