What does it mean when people write...?

[Mikey Dee]

for example-
#RealTalk
like what does the "#" mean?? i dont get it! all u twitter people can u helpp please?

[zebby.27]

it's when they 'tag' something, or to show that it's a TT (trending topic).

[Mike]

I don't use twitter but I'm pretty sure that's how you create a tag. For example, when you go onto a site like Yahoo Answers, you have the categories you post your question in. Think of the # like a way of putting your tweet into a category. Except people create their own tags, instead of having a few pre-made categories.