Bait and switch: Bait and switch advertising is a link-building strategy that involves optimizing a website in a manner that attracts links, traffic and shares, and then changing the website's entire purpose once it has gained sufficient authority. Bait and switch is generally illegal outside SEO -- and when used as part of an SEO campaign, it is considered spam, not to mention unethical.
In any bait and switch strategy, two websites are typically used -- an optimized website and a "regular" website. The optimized website is ranked for keywords that aren't necessarily relevant to the company's business, but are instead keywords that have little competition -- false keywords. By using keywords that other businesses aren't using, it becomes easier for the optimized website to build targeted traffic. Once the optimized website generates a high enough ranking in the Google algorithm, it is then replaced with the "regular" website that contains non-op.
Bait and switch is categorized as a black hat SEO tactic. Most search engines have altered their algorithms to weed out tactics such as this -- so while this strategy might temporarily help generate traffic for your site, it won't last forever. Your website's search-engine rankings will eventually decrease.