Web Scraping with Ruby Using Mechanize and Nokogiri Gems
Web Scraping can most succintly be described as "Creating an API where there is none". It is mainly used to harvest data from the web that cannot be easily downloaded manually/does not provide an option for direct download. Scraped data can be used for a variety of purposes like online price comaprison, detecting changes in web page content, real-time data integration and web mashups.