how many of you earn money on twitter?

Twitter is a social media, and you don't earn money in it. You can promote your ways to make money in it, that is the Twitter's way to earn money. In example, you can use your twitter to promote your referral links of a site, your affiliate programs, your blog, your site, etc. And if you have a lot of followers you can earn a good money doing this promotions.

Oh I never know that we can earn from twitter. I have an account in twitter but I have no idea that we can generate income from them, I will check their terms and conditions first.