Google filters ads based on several factors, here are some of the prominent ones:
1. Relevance to content: This is what makes AdSense superior to all its competitors. The trait to cater ads which are relevant to the content published on the site. This is one of the key pros of using AdSense. Since this serves as a benefit for not only the site owner but also the viewer. Google AdSense determines the content published on the site and decides what ads are relevant to it, following which they are published. Being a universal program, AdSense also takes into consideration the geography as a relevance factor and with respect to the same, it decides the ads needed. A key point to be noted that, AdSense being global, isn’t restricted to English alone.
2. Appropriateness of content: Different websites offer different genre. Ranging from kid-friendly to strictly adult content. The orientations may incline towards violence, sexual content, so on. The AdSense program is available for all website owners and advertisers, long as they comply with the program policy. Google has a hand in the content displayed in the ads, publishing them in a way that there is no offense to anyone. Language filters and language experts are utilized here to govern the grounds on which ads may be displayed. Google employs strict guidelines and rules for conducting an editorial review on the content of ads published. Along with these features, Google specifically asks you what kind of ads you deem inappropriate for your site,
3. Competition filter: Websites being in multitudes, there’s always a chance of one website’s service being advertised on a rival site’s ad column since the entire exchange is content based. To prevent this from happening AdSense provides a facility to website owners to specify the possible competitors they might have, so as to ensure their ads not be displayed on your site, thereby screening them away.
4. Choose your own: AdSense facilitates for you to choose your own default ads which you want to show on your site, should there be a possibility that Google isn’t able to serve you ads of your preference, or due to unavailability.