Image source: Facebook.Over the past 20 years, advertising on the internet has evolved in two notable ways. It all started with display advertising: those annoying banner ads that most people ignore but are still all over the place. Then the industry evolved into search advertising, and Alphabet (NASDAQ: GOOG) (NASDAQ: GOOGL) rose to prominence thanks to Google's ability to target ads based on the query, which is incredibly effective since you know exactly what the user is looking for.