What is the culture medium with the biggest advertising spending on the globe? Television. Television ads are so effective for advertisers and so lucrative for TV companies, because viewers will inevitably pay attention to the advertisements. Would we be able to say the same things about content based websites, like blogs? Not exactly. If you consider Google AdSense or banner ads, the most used monetization methods, you will conclude that they practically different from the editorial content.
For instance, if you have a blog and display ads on your sidebar only your readers will be able to altogether brush off the advertisements if so they desire. A few even use ad-blockers, so they will not see your AdSense units or banners regardless where you place them.
What would the equivalent of a television ad be for a blog? Likely an advertorial, which is an article written by the advertiser about his product, and put up in the blog like an additional post. Another option is the sponsored reviews, which are posts published by the blogger critiquing a particular product or service. Most bloggers choose this example because they get to write the article content themselves, and readers will not be bothered with another writing style.