There are 2 sides to advertising. Being the advertiser or the advertisee. The advertiser would typically be the adwords user. You create campaigns on keywords that google will display for you in search results, maps, its content network, etc. This is also known as pay per click or PPC.
Being the advertisee is using something like adsense. This is where you are paid advertising money to give google a space on your site to place ads. Every customer who clicks on the ad earns you some money, depending on the bid value they advertiser has placed on that ad group.
There are other advertising networks available, but its probably best to focus on affiliate programs targeted to your niche. Check out our affiliate section for more information there.
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