How do you use hashtags (#) on Twitter and Facebook?

[Chris]

OK, here you go... hashtags 101 :

Hashtags are used to help you search for and keep track of things (conversations, trending topics, etc..) on Twitter. For example, I tweet about job search. So in a typical tweet, I may say something like;
#jobseekers - Check out my #blog for helpful information re: #resume and #jobsearch tips.

So, if a person did a search on any of those hashtaged words, my tweet would show up in their search.

Get it?
There are some hashtags that are ALWAYS used, for example, #followfriday, #jobs, #obama, #newyorktimes.... etc....
Others are temporary and may be used if a particular story is trending in the news, for example, #spaceshuttle or perhaps a popular celebrity #justinbieber - really, the ideas are endless.
Some people try to START a trend by using a hashtag in front of .... well... whatever they want to, really. At this writing #TheWayISeeIt is trending in New York. Someone started it for whatever reason and others saw it and jumped on board.

There are many sources for more information on hashtags. Here are a few that you can check out. I didn't get it at first, but now that I use Twitter for a REASON, I think hashtags are great. They can really help you to narrow down your search.