Online advertising has grown exponentially in the last decade as you can see in the success of companies such as Google and Facebook. They have grown be multi-billion dollar businesses just by tapping into online advertising market. More and more businesses are moving their marketing spend from offline advertising such as newspaper and billboards to online media such as search results and videos. While there is no denying that the online advertising can provide great value you need to be careful about where and how you spend your marketing dollars to get the most return from your marketing investment. It helps to have a basic understanding of online advertising as well as figuring out how those ads are being placed.