A woman looks at the internet site Pinterest.com on March 13, 2012. (KAREN BLEIER/AFP/GETTY IMAGES)

This piece originally appeared on the WaPo Labs Blog on July 5.WaPo Labs is the digital team at the Washington Post Company focused on innovation and experimenting with emerging technologies.

Women are from Pinterest; men are from Reddit.

This social media gender breakdown may not be all that surprising, considering that Pinterestdescribes itself as a place to “organize and share all the beautiful things you find on the Web,” and that “people use pinboards to plan their weddings, decorate their homes, and organize their favorite recipes,” while Reddit explains, “users like you provide all of the content and decide, through voting, what’s good and what’s junk.”

But when it comes to the industry as a whole, which sex is more actively tweeting, posting, tagging, and friending?

The fairer of the two, by 99 million social media visits per month. Surprised?

According to an infographic by marketing firmDigitalFlashNYC, 56 percent of social media users – 81 million people – are women. To put this number in perspective: 81 million individuals could fill every single sports stadium in the U.S. more than seven times over. (What event could prompt such a massive gathering is unclear – the Pinterest Olympics?) And it’s not just social media sites specifically targeted towards women – Facebook is skews female by 58 percent, and Twitter by 64 percent.

Even online gaming has become female territory – 60 percent of Zynga users are women,according to the graphic, and it’s not just tweens playing Farmville: women over the age of 55 spend more time playing games online than men aged 15 – 24 and 25 – 34 combined. That’s a lot of triple word scores for granny.

So where are the online man caves? In addition to Reddit, where men outnumber women five to one, Google+ is male territory (71 percent), and so is LinkedIn (63 percent). In fact, there are more men using LinkedIn than women on LinkedIn, Reddit, and Google+ added together.

The virtual battle lines may have been drawn, but there’s at least one reason to take heart: both sexes cite keeping in touch with family as the number one reason they visit social media sites. Aww. Maybe we can all just get along, after all.

For more, check out DigitalFlashNYC’s infographic on Mashable.

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