Google will explain exactly why that ad is targeting you

Google announced that it will offer greater transparency about its system of advertising, thus allowing users to learn why certain ads appears as search results, as well as their Gmail account.

With the new redesigned Gmail comes option Why these ads, which can be found next to each ad that is shown in Gmail or results in Google search. By clicking on this link, you can find information on just that ad has appeared. According to blog of Google, the combination of geographic location, language, and various other indicators, allows to show those ads that are most suited. With these ads, Google wants to help users quickly find what they seek.

Users are also able to go to option Ads Preferences Manager and make changes to improve the ads that appear. So, from here you can block ads that are not interested in, or completely shut down the system for personalized advertising.