The cool kids at Facebook Inc. are telling e-laughers everywhere that “haha” and emoji are in, and “lol” is out.

Facebook last week released a report analyzing how its users convey laughter. The way they expressed humor changed based on gender, age and geography. No joke: “lol” users are older than “haha” and “hehe” people. If you want to telegraph your youthful giggles, use an emoji.

“Haha”...