Laughter was identified by haha, hehe, emoji, and LOL.

At least 15 percent of posts had some sort of laughter included in the week Facebook studied.

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The most common, haha, was used by 51 percent of users, followed by emoji (33 percent) and then hehe (13 percent).

LOL was used just under 2 percent of the time.

And it also was broken down by gender and location.

Men like hehe. Women prefer emoji.

Chicago and New York use emoji. Seattle and San Francisco are haha'ers.