A plain-language explanation
A 301 redirect is a server response that informs browsers and robots that a resource has been permanently moved to another address.
Where it helps in practice
A permanent redirect says a resource has moved and should point directly to the closest equivalent content.
The decision before implementation
Prepare an old-to-new map, update internal links and avoid chains or sending every removed URL to the home page.
How to verify the result
Check status codes, loops, canonicals, sitemaps, logs and preservation of traffic and links after reindexing.
