Yes, it all depends on the type of business online that you create. There are SO many different sites you can make to earn money.
You can make what is called "Infoprenure Website"; or a sales website; or a service website, etc.
It depends on what topic or theme you focus on; if you want to sell a product or products, if if you can do something for others such as website design, or massage therapist, or whatever type of service.
With Infopreneur site, you give a lot of unique information to your visitors, and in turn, if they purchase something, places like Amazon.com and eBay will give you some of the commission.
Also on these types of sites, you can set up Google Adsense, which is a CPC program. Depending on the topic of your site and how well-placed your keywords are (SEO), you can make some pretty nice money.
If your keywords aren't good ones, or your site isn't built properly, then you will make less money on Google Adsense and things like this.
All depends on your theme of your website!
(However, you don't need a website to earn money online, either, but having a website makes it MUCH easier.
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