US President Barack Obama has joined Facebook, using his first message on the social network to encourage people to get onboard efforts to address climate change.
"Hello, Facebook! I finally got my very own page," the President says in his first post. "I hope you'll think of this as a place where we can have real conversations about the most important issues facing our country – a place where you can hear directly from me, and share your own thoughts and stories."
Mr Obama goes on to promise there will be some "just-for-fun stuff" on the page too, before leading Facebook viewers on a virtual walk around his backyard.
"This has been my backyard for the last seven years, it also happens to be a national park," he says.
"A lot of what I do is just think about how I want to make sure the beauty of this particular national park, but also national parks all across the country and our planet, are going to be there for Malia, Sasha, their kids, their grandkids for generations to come."
Mr Obama then urges people to join him in "speaking out on climate change and educating your friends about why this issue is so important".
"At a time when nearly three in four adults online use Facebook, this feels like a great place to do it."
His post comes just weeks before a major United Nations climate change conference is held in Paris.
Mr Obama also has a public Facebook page listing him as politician, rather than President.