Technisches SEO

A 301 redirect is an HTTP status code permanently redirecting one URL to another — the standard for URL changes, domain moves and site migrations.

Structured markup of a page's author via Schema.org `Person` with a `sameAs` array of profile URLs (LinkedIn, ORCID, Mastodon) — supports E-E-A-T and knowledge graph entity recognition.

B2B shops with login have SEO-specific challenges — most of the catalog and prices sit behind auth, classic crawling logic doesn't apply. SEO concentrates on public funnel pages.

Microsoft's search engine with its own index and crawler (Bingbot) — also powers DuckDuckGo, Yahoo, Ecosia, and ChatGPT Search, making it worth more market share than Bing's direct usage suggests.

Microsoft's free tool for monitoring Bing visibility — index status, crawl errors, keyword reports, and URL submission. The Bing-index counterpart to Google Search Console.

Microsoft Bing's official web crawler, which captures pages for the Bing index and is therefore also indirectly relevant for DuckDuckGo, Yahoo, and Bing-based AI answers.

Search engine from the Brave browser company with its own index — privacy-focused and one of the few fully independent indexes alongside Google, Bing, and Yandex.

Server-side compression methods that shrink text resources like HTML, CSS and JavaScript before transmission — Brotli usually delivers better ratios than Gzip today.

A distributed server network that delivers static — and increasingly dynamic — content from the geographically nearest edge server to the user.

CLS measures unexpected layout shifts during page load. A Core Web Vital — "good" is ≤ 0.1 (unitless score).

Core Web Vitals are three Google metrics (LCP, INP, CLS) measuring loading speed, interactivity and visual stability of a page — part of the Page Experience signals.

Crawl budget is the number of URLs Googlebot crawls on a website within a given time frame — determined by server load and the perceived popularity of the content.

The speed at which a search-engine crawler issues requests to a site — measured in requests per second or per day and automatically adjusted to server response time.

An automated program that systematically visits web pages, reads their content, and follows links — the foundation for search-engine indices, monitoring tools, and AI training data.

The critical rendering path is the sequence the browser runs to turn HTML/CSS/JS into pixels parsing, render tree, layout, paint. Optimizing it shortens first paint and LCP.

CrUX is Google's public field-data dataset of real performance values from Chrome users (opt-in). It's the source of Core Web Vitals scoring in Search Console and PageSpeed Insights — not synthetic.

Privacy-focused search engine that draws results primarily from the Bing index and enriches them with its own sources (Wikipedia, Apple Maps, the DuckDuckBot crawler).

Faceted navigation refers to filter and sort URLs in shops and listings (color, size, price). It quickly generates millions of crawl URLs — a crawl-budget killer without robots.txt, noindex, or parameter handling.

FCP measures when the browser renders the first visible DOM element (text, image, SVG). "Good" at ≤ 1.8 s. The earliest signal that the page is responding — not a Core Web Vital, but an important PageSpeed metric.

Field data are real performance values from actual users (CrUX, RUM). Lab data are synthetic measurements under controlled conditions (Lighthouse, WebPageTest). Google ranks by field data — lab data only hints at trends.

The current generation of Google's web analytics tool — an event-based data model rather than the session-based Universal Analytics. The sole standard since July 2023, Universal Analytics has been shut down.

Free Google tool for monitoring a site's visibility in the Google index — performance reports, index coverage, Core Web Vitals data, and URL inspection. A mandatory SEO tool.

Googlebot is Google's web crawler that discovers, downloads, and processes pages for the search index. Operates in two main variants — Smartphone and Desktop.

Hreflang is an HTML/header attribute telling search engines which language and regional versions of a page exist — crucial for multilingual sites.

Modern versions of the HTTP protocol that deliver parallel requests over a single connection (HTTP/2) or via the faster QUIC transport (HTTP/3).

The process by which static HTML rendered on the server is retroactively given JavaScript interactivity in the browser — turning "dead" markup into a reactive app.

Using modern image formats (WebP, AVIF) plus appropriate sizes and compression to dramatically shrink image payloads without visible quality loss.

Indexing is the process by which a search engine analyzes a crawled URL and adds it to its search index. Crawling ≠ indexing — they are separate steps.

INP measures how quickly a page responds to user interactions. A Core Web Vital since March 2024 (replacing FID) — "good" threshold is ≤ 200 ms.

International SEO controls which language and country version of a site ranks in which market. hreflang is the central signal — bidirectional, with an x-default fallback and consistent canonicals per locale.

Googlebot renders JavaScript pages in two stages — first an HTML crawl, then rendering via the Web Rendering Service (Chromium-based). The delay can hold up indexing of client-rendered content.

A discipline within technical SEO that ensures JavaScript-rendered content is correctly crawled, rendered, and indexed by search engines.

Paid, ad-free search engine that aggregates results from its own crawlers (Teclis, TinyGem) and API sources — targeted at users willing to pay for ad-free, quality-filtered search.

Lazy loading is a technique where images, iframes, or JavaScript modules load only when actually needed — usually when scrolled into the viewport.

LCP measures when the largest visible element in the viewport finishes loading. Part of Core Web Vitals — the "good" threshold is ≤ 2.5 s.

Lighthouse is Google's open-source audit tool that synthetically measures a page's performance, accessibility, best practices, and SEO in a controlled environment.

Crawlers from AI providers that gather web content for training or live answers. Examples — GPTBot, ClaudeBot, PerplexityBot, Google-Extended.

Log file analysis evaluates server logs to see which URLs Googlebot actually crawls, how often, and with which status code. Reveals real crawl behavior — unlike Search Console (aggregated) or synthetic crawlers.

An indexing mode where Google primarily uses the mobile version of a page for crawling, indexing, and ranking. The default for all sites since July 2024.

News SEO is the SEO discipline for news-oriented sites — speed, freshness, news sitemap, NewsArticle schema, and inclusion in Google News and Top Stories are the levers.

Robots directives that control whether a page gets indexed or its links followed. Set via the meta robots tag or the X-Robots-Tag HTTP header.

PageSpeed Insights is Google's free web tool that combines Lighthouse lab scores with CrUX field data from real Chrome users and outputs concrete optimization suggestions.

Resource hints in the HTML head that tell the browser to fetch resources earlier, set up connections in advance, or accelerate DNS lookups.

Render-blocking resources are CSS and JavaScript files the browser must load and parse before it can render. They delay FCP and LCP — minimize them with async/defer, inline critical CSS, and remove unused CSS.

robots.txt is a text file at a domain's root telling search-engine crawlers which URLs may be crawled and which must not.

SERP stands for Search Engine Results Page — the result page Google, Bing and other search engines return for a given query.

SERP features are all display elements in search results beyond the classic blue links — featured snippets, People Also Ask, knowledge panel, local pack, image, video, and shopping boxes.

A sitemap is an XML file listing all relevant URLs of a website — it helps search engines crawl and index large sites systematically.

A soft 404 is a page with no real content (out-of-stock product, empty search) that incorrectly returns HTTP 200 instead of 404/410. Google usually detects it and reports it in Search Console.

Spam updates are regular Google algorithm adjustments that detect manipulative SEO tactics and remove or sharply demote affected pages in search results.

Two opposing render strategies for web pages — either the server generates ready-made HTML (SSR) or the browser assembles the page via JavaScript (CSR).

Structured data is machine-readable markup in HTML — typically using the Schema.org vocabulary in JSON-LD format — that explains a page's content precisely to search engines.

TTFB measures the time from request start to the first byte received. It sums DNS, TCP, TLS, and server processing. Rule of thumb — good < 200 ms, problematic > 600 ms; directly affects LCP and FCP.

Aggregated visibility score for a domain in the Google index, computed by SEO suites (Sistrix, Searchmetrics, Semrush) from their own crawls — useful for trend comparison, but not a Google signal.

HTTP header that sets robots directives (e.g. noindex, nofollow) at the server level — also works for non-HTML resources like PDFs, images, or JSON responses.