Twitter co-founder Evan Williams snipes at Facebook and Instagram

Twitter, or rather one of the social network’s co-founders, Evan Williams, has hit back at Facebook and Instagram following the recent revelation that the latter had edged ahead of Twitter in terms of monthly active users.

Instagram announced last week that it had racked up 300 million users, more than Twitter which has around 285 million, and CEO Kevin Systrom was obviously pretty pleased to reveal this fact.

Williams, however, told Fortune magazine (via The Register) that there was too much focus on monthly users driven by Zuckerberg and co, and he argued that this was the wrong metric to focus on. Williams said that Twitter was making more money than Instagram – a “hell of a lot more” in fact – and was indeed a more important site in general.

Williams commented: “If you think about the impact Twitter has on the world versus Instagram, it’s pretty significant. It’s at least apples to oranges. Twitter is what we wanted it to be. It’s this realtime information network where everything in the world that happens on Twitter – important stuff breaks on Twitter and world leaders have conversations on Twitter.”

“If that’s happening, I frankly don’t give a shit if Instagram has more people looking at pretty pictures.”

Williams pointed out that the way Facebook defines an active user, it includes folks who might not have visited Facebook at all in the month, but have shared something via a third-party app that they used their Facebook account to sign up for. In this case – say they’ve simply liked a song on a streaming music service – they still count as an active user, which is playing with the boundaries of the definition.