SEO Wiki.

When you open a crawl in Screaming Frog, every red filter hides a technical SEO concept: a response code, a meta tag, a server rule, a way of building URLs. Understanding what lies behind it is the first step to deciding whether to act, and with what priority.

Here you’ll find those concepts explained in brief, grouped into four areas: server responses, page code, infrastructure and site structure. Each entry tells you what the issue is, why it matters for search engines and AI answer engines, and how to spot it in your crawl data. A few minutes per entry is enough: read them when a report shows you something that doesn’t add up, before opening a ticket with the development team.