Do you keep seeing the # in Twitter posts and wonder what the heck it is? Well this is an easy way to tag your Twitter posts. There is a service called Hashtags. This service aggregates those tags to find out what is happening now on Twitter. Simply place a # before you tag. Just note that you can only tag a single word (i.e #coolshades vs. #cool shades). The second example would only use the tag "cool".
Tip: Also something to note is that the site creates a user page that lists out your recent tweets. This generates a dofollow link back to your Twitter profile. If you use the full URL in your tweet they are also dofollows. Sometimes it pays to use the original URL versus using a tiny URL.