Just Call It The "At Symbol"
The "at symbol" (@) does not have a specific word in English. Although writers have made suggestions, none stuck. Though the symbol dates back to 1536, it was brought out of obscurity in 1971 when computer scientist Ray Tomlinson, the inventor of email, decided to use @ in email addresses.
Key Facts In This Video
The Apple control is actually called a "gorgon loop." (0:25)
The stick and the circle in the symbol for "power" represents a 1 for "on" an a 0 for "off." (0:43)
The symbol for USB is supposedly based on the shape of Neptune's trident. (0:54)