Google

Google is the world's most-used search engine and the practical benchmark for index size and result quality. For most people it is the default entry point to the web, and for site owners it is the traffic source that matters most.

Beyond plain keyword search it carries a large set of operators worth knowing: site: restricts results to one domain, filetype: finds documents of a given type, quotation marks force exact phrases, and the Tools menu filters by date — together these turn a vague query into a precise one.

Results are personalized by location, language and history, so what you see is not necessarily what a user in another country sees. When checking how a page actually ranks abroad, use a clean browser profile or a location-specific check rather than your own logged-in session.