In February $2006,$ BMW was caught manipulating search results for the term 'used car' by redirecting searchers to the regular BMW company page when they clicked through. For this, the site was completely removed from search results for three days. This is an example of black$-$hat SEO which is any practice that

is no longer used by web developers

is designed to artificially boost rankings

improves search engine rankings

improves search results by not including inbound links from other pages