In computers, Ultra Advanced Technology Attachment (UATA) is a term used to describe a type of hard disk drive (HDD). HDDs are a non-volatile way of storing digitally encoded data. Non-volatile means that the data remains on the HDD even when it is powered down, although the data can only be retrieved when the HDD has power. By contrast, a computer chip that stores digital information that is volatile loses that information when the device that it is housed within is powered down. Advanced Technology Attachment is a general class of HDDs and Ultra distinguishes a more specific type of HDD from that general class.
UATA and ATA HDDs are more commonly referred to as Integrated Drive Electronics (IDE) HDDs. In technical terms, IDE refers to the connection between the hard drive and the computer. Formerly, a hard disk's controller could be found on the main circuit board of a computer or on an expansion card plugged into the main circuit board of a computer. By contrast, an ATA/IDE hard disk's controller is integrated into the HDD's assembly itself. IDE is also used to distinguish the ATA/IDE class of HDDs from the HDDs that preceded them.
The role of the controller is to manage the transfer of information from one part of a computer system to another part of the system. By relocating the controller, an ATA/IDE HDD can now be described as self-governing. Now, a controller that is integrated into the UATA drive manages data transfer instead of the controller found on the computer system to which it was attached. This in turn was seen to reduce compatibility issues between data transfer methods of hard drives and computer systems. In UATA hard drives, AT refers to the use of IDE/ATA drives.
The U, or Ultra, indicates that a particular ATA/IDE HDD uses a method of data transfer called Ultra direct memory access (DMA), or UDMA for short. UDMA appeared first in 1998 and, at its fastest, it was twice as fast at transferring data at 33/MegaBits per second (MB/s) than DMA. DMA was a step forward in data transfer methods in that it achieved higher transfer rates by avoiding the Central Processing Unit and communicating directly with the a computer’s memory for data transfer tasks. UATA hard disk drives that currently use the UDMA data transfer methods based on a technique called bus mastering can transfer data at a rate of 133 MB/s. This is a relatively new technology that allows the computer to handle more than one task at a time without affecting the speed or outcome of each task.