# What do “underfull” warnings mean? [duplicate]

What does this warning message mean?

Underfull \hbox (badness 10000) in paragraph at lines 49--50

This is my code, I can't see what happens, it is a simple itemize. As you see, there is an admiration symbol, I don't know what is going on.

I have also this warning, another admiration symbol:

Underfull \hbox (badness 6893) in paragraph at lines 77--78

I am working in article as class document. That is just text, no reference mode.