What does # stand for on the internet?

[Nicole]

Ok, I've seen alot of # like #throwbackthursday, #happyfriday, #windows, etc. on Facebook, Youtube, Twitter, EVERYWHERE and I want to know what it means! Anyone know? Thanks in advance!

[I Like Stories]

# tag is a uniquely twitter thing. It's meaningless across the Internet at large.

Twitter uses it like a keyword. When you go to twitter and search on #"phrase" you will see everyone's tweet that uses that hash tag.

[Jillian]

People use it on instagram the most. It's hashtags and when you click it, it goes to a whole bunch of pictures that have been hashtagged with what ever word was the hashtag. I look at it as a good way to label your pictures. Like if someone wanted to see some quotes, they would type in #quotes on the hashtag button on instagram, and they would see a whole bunch of quotes that people have posted. Or you would search #funny and then you would see a whole bunch of funny pictures.

[David E]

It is a tag for your post so that search engines can find similar posts. Here are some examples

https://twitter.com/search?q=%23happyfriday&src=typd #happyfriday
https://twitter.com/search?q=%23indycar&src=typd #indycar

Both those show you posts on a theme.

Oh, and here is one for this forum https://twitter.com/search?q=%23yahooanswers&src=typd