search engine - What is the difference between web-crawling and web-scraping? -


is there difference between crawling , web-scraping?

if there's difference, what's best method use in order collect web data supply database later use in customised search engine?

crawling google, yahoo, msn, etc. do, looking information. scraping targeted @ websites, specfic data, e.g. price comparison, coded quite differently.

usually scraper bespoke websites supposed scraping, , doing things (good) crawler wouldn't do, i.e.:

  • have no regard robots.txt
  • identify browser
  • submit forms data
  • execute javascript (if required act user)

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