Web data glossary

Anti-bot detection is the set of techniques a website uses to tell automated traffic from human visitors, such as CAPTCHAs, fingerprinting, and rate checks, in order to block or challenge scrapers and bots.

A CSS selector is a pattern that points at specific elements in an HTML document by tag, class, id, or position, originally for styling but widely used to locate values when scraping a page.

A headless browser is a real web browser that runs without a visible window, controlled by code, so it can load pages, run JavaScript, and render content exactly as a normal browser would, just without a screen.

JSON Schema is a vocabulary for describing the shape of a JSON document, used to declare which fields you expect and what type each one should be (string, number, boolean, array, or object).

LLM data extraction is the use of a large language model to read content and pull out specific fields by meaning, rather than by fixed rules like CSS selectors, returning structured values from unstructured text.

Rate limiting is the practice of capping how many requests a client can make in a given window of time, used to protect servers from overload and to keep automated traffic polite and predictable.

Structured data extraction is the process of turning unstructured or semi-structured content, such as a web page, into clean records that follow a predefined shape with named, typed fields.

A web scraping API is an HTTP service that fetches and reads web pages on your behalf and returns the extracted data, so you call an endpoint instead of running and maintaining your own scraper.