What does it mean when a girl puts a "<3" at the end of a text?

[taylor frederick]

This girl I like couldn't sleep so she posted something to Twitter about still being awake at 4 in the morning. I was surprisingly up at this time and tweeted her and she then texted me and started putting hearts and smileys at the end of her tweets and texts. She said she misses me and then she tweeted "Think I might like him(: #crushing #happy" while we were texting I didn't ask if it was about me though. Could that be me she was talking about? I know she hangs out with other guys but she also tweeted that "making a girl smile is the best thing anyone could do(:"

[Caleb]

I love you

[Harvey]

look at it its a penis

[SoScorpio]

It's supposed to look like a heart

[Linus Upp]

Keep texting. I have shares in the phone company.

[Mrs. Fitzherbert]

She likes you please answer mine, the second question on my profile, thanks

[. . . .]

aww that sounded really sweet she probably likes you , i dont think those other guys were up at '4' .
gud luk hpe evryfin gos gudxxxx

[Megan]

she likes you ...trust me i know , thats what i do , ask her out. good luck go on my profile and answer my questions please? theres only 2 short ones and i really could use peoples help x

[Wuzzlebaby]

Are guys really that clueless? Most likely. I'd say she was referring to you. Best thing to do, if you want to be with her, is ask... If you don't want to get involved with her though, leave it alone.