Download the logo by right-clicking (secondary-clicking) the image above and selecting "Save As..." or similar option.
If you've been linked to this, you probably made a language mistake and whoever sent this to you cared enough to point it out. The best thing to do is read the details and see where you went wrong.
Hashtags are words or phrases preceded by a "#" symbol to mark topics of interest on various social networking sites. The symbol itself is known as a "hash" or "hash mark", and the combination of the symbol and word(s) is a hashtag. So it is incorrect to read "#grammar" as "hashtag grammar"; "hash grammar" is more correct.
Logo and details are available under the Standard Free License. Please credit this page or any of the accounts listed on my homepage.