One of the most beautiful and exciting qualities about blogging is that you can create a blog that deals with any subject area that you are either knowledgeable or passionate about (and preferably both!). You can write about personal finance, careers, real estate, getting into business, technology, cooking, travel, personal health, or just about any topic you choose.
One of the cool things about Google AdSense is that it's so easy to get set up. If you have a blog or website, you can sign up for a free Google AdSense Account. From there, Google will give you a unique code that you will paste onto your website. Google takes it from there, tracking your page views, traffic, and earnings on your behalf. There is no upkeep or maintenance to get this thing going, which makes it a no-brainer if you have a website already.