Rather than making money through subscriptions, YouTube channels are based on a traditional advertising system. Meaning the more viewers you get, the more you make. Once you’re approved for the YouTube Partner Program and can start including ads on your videos, with every 1,000 views, you will make approximately $2-$4. Which might not seem like a lot, but if you have 100 videos with 5,000 views a month each, that would be $1,000–$2,000 already. Just imagine if your videos start hitting millions of views!
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.