Facebook status..what does it mean when you type # with words all ran together after?

[♥]

example .... someone types their status then "#notphasingme"

[Taryn]

its a tag, used to categorize something like

mall #shopping

basketball #sports

or used to categorize something in a trend of some sort.

[Pjay]

It's called a hashtag. It's more a Twitter thing than a Facebook thing. Everything with a given hashtag will end up on a page with that name on Twitter.

[HayleyHazard♥]

Its not even supposed to be used on Facebook.
It is a Twitter hashtag.
A hashtag is basically the number symbol(#), with words bunched together afterwards.
On Twitter, it lights up light blue and you can click on it.
Its where you type something with the hashtag in front of it and you can see if its trending.
Example;
Watching heat play....get it boys... #notphasingme
Idiots of Facebook picked up on it to try and look cool.
Tried to explain it as best as I could. (: