seoder

Glossary

One term per page, each with the definition first and the practical consequence second.

  • Canonical URL

    The canonical URL is the address you nominate as the real one for duplicate content. How the link rel canonical hint works and why it is a hint, not a rule.

  • Cloaking

    Cloaking is serving crawlers different content than users. Where the line sits, why the intent test is unreliable, and the setups that cross it by accident.

  • Crawl budget

    Crawl budget is how many URLs a crawler will fetch from your host in a period. What sets it, what wastes it, and why most sites do not have a budget problem.

  • Hydration

    Hydration attaches JavaScript behavior to server-rendered HTML in the browser. Why crawlers do not care about it and users do, plus the hydration mismatch.

  • JavaScript rendering

    Whether a crawler executes your JavaScript before reading the page. Which crawlers do, what the raw versus rendered comparison shows, and what it costs.

  • llms.txt

    llms.txt is a proposed markdown file describing a site for language models. What it contains, what it is not, and which operators have committed to reading it.

  • noindex

    The noindex directive tells a search engine to keep a page out of its index. Where to put it, how it differs from Disallow, and why the two cancel out.

  • Prerendering

    Prerendering produces finished HTML before the request arrives or at the edge. How it differs from server rendering, and when it becomes cloaking.

  • robots.txt

    What robots.txt is, how crawlers match its groups, what a missing or failing file means, and the two mistakes that make a correct-looking file do nothing.

  • Soft 404

    A soft 404 is a missing page served with a 200 status. Why crawlers keep requesting it, how search engines detect it, and the correct status code to return.

  • Time to first byte

    TTFB is the delay between a request and the first byte of the response. What it includes, why crawlers care about it, and why it is not a ranking factor.

  • X-Robots-Tag

    The HTTP header form of the robots meta tag. What it controls, why non-HTML files need it, and the scoping mistake that deindexes more than intended.