Hmm..

'Hmm..'
very often used and mostly worked expression on messenger. It does not carry any meaning by itself. But helps a lot as in...

a: "R u still in office?"
b: "Hmm.."
a: "Busy kya?"
b: "Hmm.."
a: "Ok, ttyl"
b: "Hmm..."

or..

c:"I love you"
b: "Hmm..."
c: "Do you love me?"
b: "Hmm.."

or..

d: "You write nice blogs.."
b: "Hmm.."
d: "Most of your posts have been posted during office time"
b: "Hmm.."
d: "Don't u have any work?"
b: "Hmm.."

"Now don't you think it's quite lame post?"
Hmm..