AT may refer to any of the following:
1. Short for advanced technology, AT is an IBM computer first introduced in 1984. The base model AT computer contained an 80286 processor, 256 k of RAM and a 1.2 MB floppy disk drive. The AT was also available with 512 k of RAM and a 20 Mbyte disk drive. Today, an AT-class system is any computer with a 16-bit, 32-bit, or 64-bit system. Earlier computers (8-bit) were known as PC/XT-class systems. All new computers used today are considered AT-class computers and you're not likely to encounter earlier computers. A PC/XT-class computer can be identified if it is using the older 8-bit ISA expansion slot.
2. Ampersat, asperand, arobase, at, at sign, or at symbol is the name of the " @ " symbol found above the 2 on a U.S. keyboard. When describing an e-mail address, it may be described as "support - at - computerhope - dot - com," which is the same as [email protected]
How to create the @ symbol
Creating the @ symbol on a U.S. keyboard
To create the at symbol using an Apple keyboard, hold down the Option key and press the number 2 at the top of the keyboard.
Creating the @ symbol on a smartphone or tablet
Creating the @ symbol on keyboards outside of the U.S.
Computer users in other parts of the world, such as Italy, can find the @ symbol on a different key. In the picture below is a keyboard key with the @ symbol on the same key as the Ç and Ò key. To use this key, hold down the Alt key and press the key with the at symbol on it.
Where is the at sign key on the keyboard?
Below is an overview of a U.S. computer keyboard with the at sign key highlighted in blue.
How is the at symbol used on a computer?
Below are examples of what uses the at symbol on a computer.
- E-mail address.
- Array in computer programming.
- A short way of saying "at" in chat or a text message.
- In a batch file to not echo to the screen.
- Placing the @ symbol in front of a username on Twitter directs the tweet to that user.
4. Windows command line command. See the at command page for further information.
5. Linux command. See the Linux at command page for additional information.
6. Modem strings used to initialize and control a computer modem. See the Modem AT commands page for a listing of the basic Hayes compatible legacy modem AT strings. In the picture, is an example of an AT string.
7. A Full AT is another name for the Full AT motherboard.
8. AT keyboard is a Din 5 port used with early IBM keyboards. See our AT keyboard page for further information about this port.
9. AT is short for Azores Time.