Key Difference: AdWords allows one to promote his or her business by placing ads on the internet, while AdSense allows one to earn money by showing the said ads on their websites.

AdSense and AdWords are two different advertising programs by Google. They are interrelated and can even be said that to be two sides of the same advertising program. AdWords allows one to promote his or her business by placing ads on the internet, while AdSense allows one to earn money by showing the said ads on their websites.

Google Adsense is a program by Google that allows people in the Google Network of content sites to show ads on their websites. These ads can be automatic text, image, video, or interactive media advertisements. These allow the publishers to earn money. The ads are targeted to the site’s content and audiences, which increases the chances that the ads would be relevant. The ads are administered, sorted, and maintained by Google and can generate revenue on either a per-click or per-impression basis.

A pay per click (PPC) system is where the publisher is paid according to the number of times that the viewers have clicked on the ad. Whereas, a cost per impression (CPI) is there the publisher is paid for how many people have viewed the ad on their site. CPI is usually calculated on the basis on a thousand views.

The ads are regulated by Google and are shown on the basis of its relation to website content, the user's geographical location, and other factors. This makes the ads quite relevant to the viewer, which is what has increased the popularity of Google Adsense over other competitive advertising programs. In fact, Adsense is one of the most commonly used advertising programs to monetize content. It is particularly popular with small websites that do not have the resources for developing advertising sales programs and sales people to generate revenue with.

The ads that are showcased on the website through Google Adsense are by advertisers who are part of Google Adwords. Google Adwords is an online advertising service provided by Google in which companies pay to show their ads on various sites. These ads can be shown on at the top or bottom of the Google Search results pages, as well as the side of the Google Search results pages and on other partner sites in Google Adsense.

The ads are linked with relevant keywords and are shown either when these keywords are searched (in context of the Google Search results pages) or when the keywords are associated with the content on the webpage (in context of the partner sites). AdWords offers pay-per-click, or rather, cost-per-click (CPC) advertising, cost-per-thousand-impressions or cost-per-mille (CPM) advertising, and site-targeted advertising for text, banner, and rich-media ads. It also allows advertisers to choose from local, national, and international distribution.

Due to the reach and popularity of Google Adsense among publishers, Google Adsense has also grown in popularity with advertisers. It is one of the most popular advertising programs available today. In fact, it is the main source of Google’s revenue.

Comparison between AdSense and AdWords:

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