QDialogButtonBox

A 301 is a permanent redirect: it tells search engines the page has moved for good, passes the ranking signals along to the new URL, and the target replaces the source in the index. A 302 (and its stricter siblings 303 and 307) is temporary: it says "the page is briefly somewhere else, keep the original indexed." The practical trap is using a 302 for a move that is actually permanent — you keep the old URL in the index and you don't cleanly consolidate ranking signals onto the new one. For a permanent move, always use a 301 (or 308, its method-preserving equivalent).

Yes, a little, and it adds up. Every extra hop is another request the browser and the crawler have to make before reaching real content, so the page feels slower and each redirect can shed a small amount of link equity. Google generally follows several hops, but it doesn't have to follow forever, and long chains waste crawl budget on large sites. The fix is simple: keep it to a single hop by pointing the source URL straight at the final destination instead of at another redirect. If page A redirects to B redirects to C, update A to point directly at C.

A 404 means "not found" — the page is missing, but it might come back, so search engines keep checking for a while. A 410 means "gone" — you removed it on purpose and it isn't returning. When you deliberately retire a page and have nothing to redirect it to, a 410 tells crawlers to drop it from the index faster and more cleanly than a 404, and it stops them re-requesting a URL you never intend to restore. Use a 301 when there is a good replacement to send visitors to; use a 410 when the page is genuinely gone and a redirect would be misleading.

A redirect loop happens when URLs send visitors back and forth without ever landing on a real page - A redirects to B and B redirects back to A, so the browser gives up with a too many redirects error. Find the cycle by tracing the chain (this tool stops and flags it), then break it: decide on one canonical destination and make everything point there, or turn one of the URLs into a real 200 page. Common causes are conflicting rules - one for HTTP to HTTPS and another for www that disagree, or a trailing-slash rule fighting a CMS redirect. Solve the conflict so a single, consistent rule wins.