It’s what all the cool kids are doing so now we have them here.

Wiki can tell you more about hashtags.

Just preface any word with a # and it’ll be auto-magically-linked to a page of other articles containing the same one.

Example: #crafts

Some day I’ll go through and hashtag all the existing articles. #myworkisneverdone

PS- you can also hit the little magnifying glass in the top left corner to search for other things.

#tcr