At sign

The at sign (@) is a logogram. It is used in bills, emails and programming. 

Bills

In bills, it means "at a rate of". For example, 7 widgets @ £2 equals £14.

Emails

In email, it shows a specific domain of an email address.  

Programming

In programming, the at sign has been used in several programming languages. Using the at sign in programming was invented by Ray Tomlinson. It is the ligature form of the Latin word "ad", which means "at". The sign is one of several special symbols on the standard English keyboard.

Footnotes

Category:Symbols
Category:Typography
Category:Latin letters