There are several ways to earn a decent income from your website or blog, one of these ways is advertising.
The most popular advertising program is known as Google Adsense which as it name implies is owned by Google. Although quite difficult to get into, once you abide by all their rules and have decent traffic, you will be accepted.
Google AdSense is the most popular and one of the best ways of monetizing your blog. It is a program run by Google which if you are allowed into lets you place picture or text adverts on your blog and whenever it is clicked, you make money. The downside is that is very difficult to get into but if you adhere to their rules which are listed below, you will be able to get in. To apply go to adsense.google.com
Another way to make money through advertising on your blog is by providing ad slots for interested companies or persons to rent or lease. This works best when you have a lot of visitors, you can contact companies you believe will be interested in advertising on your blog and tell them why they should advertise with you, your main strength will be the number of visitors you have, the more the number of visitors, the more you can charge for every ad slot.
There is also another way to earn through adverts called sponsored posts, these are posts which are paid for by individuals or corporate bodies. They usually provide you with the post and images to be used and pay you for posting it on your blog. Once you have good traffic and a high online reputation, many companies will contact you to post on your blog.
Another popular advertising program is Infolinks which you can even run concurrently with Google Adsense on your blog. It is easy to get into but the downside is that they pay far less than Adsense. It uses text based advertising and you are paid for every click. To apply visit www.infolinks.com
There are many others such programs as Revenuehits.com, adversal.com, propellerads.com, etc.
The secret of making money through Advertising programs is having a large number of visitors to your site daily which is why you really have to work on Search Engine Optimization..