Stands for "Advanced Technology Attachment."
ATA was a standard interface for connecting hard drives and floppy disk drives to a computer. It integrated the controller into the drive itself so that an ATA drive did not require a separate controller card to connect to a motherboard. Following the introduction of the SATA interface in the early 2000s, the ATA interface was retroactively renamed "PATA" for "Parallel ATA."
The ATA interface used 40-pin ribbon cables to connect drives to the motherboard. These cables could include three connectors, allowing two drives to share a single cable. For the motherboard to send data to the correct drive, ATA drives had to be designated "Device 0" (the primary drive) or "Device 1" (the secondary drive) using jumpers located on the drive next to the ATA connector. Only one drive on a cable could communicate with the system at a time, and Device 0 always had higher priority. Later revisions of the ATA specification added a "cable select" mode that automatically designated roles based on which connector a drive was attached to.
The ATA standard was updated several times in the 1990s. Each new revision added new DMA transfer modes to improve drive performance. ATA-4 added ATA Packet Interface (ATAPI) commands that added support for other kinds of storage drives — optical drives, tape drives, and high-capacity removable disk drives. The final revisions, ATA-7 and ATA-8, supported data transfer speeds up to 133 Megabytes/second. ATA was eventually made obsolete by the SATA interface, which offered faster transfer speeds, a smaller connector, and support for hot swapping.
NOTE: The ATA interface was also known as the Integrated Drive Electronics (IDE) interface.