301 is one of many possible HTTP status codes, some of which you've probably heard of (including 404 - Not Found, 403 - Forbidden and, 500 - Server Error). When you visit a web page and the server sends the page normally, the status code it attaches to that page is 200 - OK. You can think of a 301 redirect like a mail forwarder. Once you've moved a piece of content away from a specific URL, anyone who tries to visit it will receive a 404 - page not found message. Now, when you attempt to visit the old URL, the server will send back the 301 - Permanently Moved status code, and then move you on to the new location. This happens so quickly that you're usually not aware of it, and will simply find yourself on the piece of content for which you'd searched. You might notice that the URL is different from the one you clicked on or typed in. Or you might have a browser extension such as Ayima Redirect Path which lets you know when you've been redirected. The other key role that a 301 redirect fulfills is with search engines. Having useful status codes that correctly signal where content has moved to allows search engines such as Google and Bing to keep their index up-to-date. Essentially, a 301 redirect will let search engines know: "Hey, you know that piece of content that users enjoyed clicking on from the SERPs? Well, it now lives over here, so take all that visibility you associated with this page, and transfer it over to this new URL."