[brey]

  if you can see or submit data using the website, it means the website does 
  have some kind of API ... For example, if you do a search in Yahoo, you can
  see the search page sent to Yahoo’s servers has the following url ...

  https://search.yahoo.com/search?p=search+term

no. no no no. this is not an API. this is about as far from an application programming INTERFACE as it can get. this means an agreed format, where there's a contract (social or otherwise) to provide stability to APPLICATION clients. there's no contract here other than 'a human types something into the box, presses some buttons and some results appears on the website'.

/search?p=search+term is an implementation detail hidden from the humans the site is built for. they can, and most likely will, change this at any time. the HTML returned (and being scraped) is an implementation detail. today, HTML. tomorrow, AJAX. next week? who knows, maybe Flash.

fine, it's a scraper builder. but don't call what it's using an API, and don't imply it's anything more than a fragile house of cards built on the shaky foundation of 'if you get noticed you're going to get banned or a cease and desist'.