301 redirect
A 301 redirect sends people and bots from an old address to a new one, and tells search engines the move is permanent.
A 301 redirect is an instruction from your server that says a page has moved for good, and where it lives now. Anyone who asks for the old address, a person or a bot, is sent on to the new one. You'll use it whenever you change a page's address, merge two pages, or move to a new domain.
It matters because old addresses don't disappear. They sit in other people's links, in bookmarks, and in the lists of pages that search engines and AI platforms already know about. A 301 keeps all of them pointing somewhere useful.
What search engines do with it
Google treats a 301 as a strong sign that the new address should replace the old one. It shows the new address in results and moves the old page's signals, like the links pointing at it, across to the new one. Google explains this in its guide to redirects, which also covers 308, the newer code that means the same thing.
For example, say Fernhill Coffee renames /coffee-club to /subscriptions. With a 301 in place, a magazine article that still links to /coffee-club sends its readers, and its credit, to the new page. Without one, they land on an error.
Redirects and AI answers
AI platforms that search the web find pages through search results and links, then fetch them. A bot that follows a link to an old address and gets a 301 lands on the right page. A bot that gets an error has nothing to read, so it can't use or cite that page.
Keep chains short, too. If /a sends to /b, which sends to /c, point /a straight at /c. Every extra hop is another chance for a bot to give up.
Redirects in AnswerOrbit
Recommendations includes fixing pages on your site that return an error to bots, and the Bot visits tab in Website shows which requests from AI bots failed, once you connect your server logs. A missing redirect after a move often shows up there first. See Website and AI traffic and Recommendations.