Is it true that users can earn money through his/her Facebook account

I don't think we can make money with a Facebook account. If we could, everyone would be using it and you wouldn't be asking this question.

But if you have a page with a million likes, you may earn money from it. You can contact some brands or companies and promote their posts on your page.

Yes, you can earn money through Facebook. I have seen many customers businesses coming up with projects like - Want 1000 unique likes. It is just like marketing, for every 1000 unique likes you will get $50 - $100. There are many such strange projects in freelancing websites. Just sign up and get a free freelance account. Check projects under Facebook or social networking, you will come to know lot about earning through Facebook. If you have 1000 friends and each of them will like page for you then you can earn money. But they will ask likes from specific location like USA, UK etc. This is one way to earn money in Facebook.

You can also develop applications and publish in Facebook. It is just like publishing app in Android and earning money. You can create game and provide in-app purchases. There may be lots of way to earn money through Facebook. If we explore more we can get the information.

Yes you can earn from Facebook. You just need to like every page in the Facebook. For that you will earn some little money in your account. There were more official links requires to like the pages in Facebook. If you like those pages you could earn more from that. These are all one sort of ways to earn.

There are multiple ways to earn money with Facebook.

Setup a Facebook page. Get many likes to this page and offer services to post ads in the page for money.

This is one of the easiest way to make money where you are basically sharing a post or article on your page for money.

I always recommend using a page and not an account for promotions, just better ethics. You can use your account to connect with people, I prefer a page for that as well.

Try to setup a niche page, build up likes and promote products, books, services which interests that niche lovers.

The answer you are looking for is 'Yes'.But unfortunately ,it isn't logical to say that you can earn via facebook,because facebook doesn't initiate or support or work along with any money earning program unlike the Google which guarantees a working earning method called 'Adsense' .Therefore ,there is nothing 'guaranteed' about earning online through Adsense.Still ,you can ,at least in name earn through Facebook but individually dealing with customers and promoting their content via your viral page etc.But indeed ,this is a time consuming process and not at all guaranteed in official terms

Facebook is one of the best source for Internet Marketing through which you can make thousands of dollars. Internet Marketing is the marketing tactics through which you promote any product or business. Most of the people are earning quite good using this techniques. This works well if you have popular pages on Facebook, where you can easily promote the product of your client and you may get great earning. Generally it depends on the owner of the page how they charge. Generally a owner will charge you Rs 1600/week for posting the link of your products on their page.
Another interesting way to earn from Facebook is to develop apps, games etc. Facebook these days are flooded with many variety's of games like Pool, City Ville, Farm Ville etc. If you are a developer then you have better scope in this field. You can develop app using Eclipse or any other platform and earn money.

Yes you can earn money through Facebook in such a way that if you own a Facebook page and someone who is interested in managing your page or someone who wants to own a page then you can lure them by saying that "Why not buy my page ?" and hence you can sell the page and earn money .

The page can be sold and money can be earned in such a way that make the buyer the manager of the page and tell him to delete your admin role from that page and hence you have sold the page and got the money .