150 million Instagram users: The social network that started in 2010 and purchased by Facebook for $1 billion in cash and stock in April 2012, now has reached the 150 million plateau at such a young age.

Instagram was already popular before it was purchased by Facebook, though 150 million users just three years into its existence is impressive. Everything Facebook touches seems to turn to gold and co-founder Mark Zuckerberg saw the potential in Instagram that Kevin Systrom and Mike Krieger saw when creating it.

During a May earnings call, Facebook chief Mark Zuckerberg said growth was the main focus for Instagram. "They're growing very quickly, and that's the right focus for them," he said. "They have this opportunity to capture and build up this huge community and that should be 100 percent of the focus right now."

His wish was granted with the now 150 million users Instagram has.

The next step that could be coming after this many users that are active is advertisement. It's now a huge venue for the social network to make a lot more revenue.

According to a new report from The Wall Street Journal, Instagram plans to begin selling ads within the year, and is currently trying to figure out how to incorporate marketing without irking users.

"We want to make money in the long term, but we don't have any short-term pressure," Instagram's director of business operations, Emily White, told the newspaper.