But more and more adults are catching on as well. Take Janet Sturley. Thanks to her houseful of teenagers — 19-year-old Ryan, 17-year-old Mark and 13-year-old Paige — she's now fluent in this mobile language.

"We'll be waiting for a table at a restaurant, and I'll look over and see all three of them on their phones," said Janet. "It's amazing — they can fill any downtime with texting."

Paige alone sends about 2,000 text messages a month. So, Janet signed up for an unlimited text-messaging plan last fall and now sends text messages to keep tabs on her teens.

"If Ryan is spending the night with a friend, he sends me a text message rather than calling," said Janet. "That way I'm not awakened at odd hours of the night, but I can check my phone at any time and know where he is."

Her kids like texting because the messages are short and direct and can be sent when a phone call isn't convenient.

"If I'm at a friend's house and I'm bored, I'll go into another room and text my mom to come and get me," said Paige. "Or, if I don't want to go somewhere, I can just text 'No, I can't' to the person who invited me instead of having to make up an excuse. That way, nobody's feelings get hurt."

Texting helps keep the Sturley family connected. And for Janet, it's a comfort to know that, even as her kids grow up and move out of the house, it won't be "goodbye" — it'll just be "ttyl." That's textspeak for "talk to you later."