Reference

Web systems glossary

Baseline
A known starting condition used for comparison.
Canonical URL
A page-provided reference to its preferred URL representation.
Crawler
Software that discovers and retrieves pages or resources by following configured sources and links.
Fixture
A controlled document or response created for a repeatable observation.
Rendering
The process that turns a source document and its resources into a document model or visual result.
Structured data
Machine-readable properties embedded in a document, commonly using JSON-LD.
Validator
Response metadata such as an ETag that helps a client determine whether content changed.