Alexa Web Search

Technology:
Alexa is gathering Web information and learning from content and paths to create the Alexa Service.
How and Why We Crawl the Web?
Alexa is continually crawling all publicly available web sites to create a series of snapshots of the Web. We use the data we collect to create features and services that are integrated parts of the free Alexa service:
Site Data: Provides information, news, and statistics about web sites
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