Key Difference: ATA stands for Advanced Technology Attachment. This name has been officially assigned by the American National Standards Institute group X3T10 to refer to Integrated Drive Electronics (IDE). SATA stands for Serial Advanced Technology Attachment. It refers to the next generation computer bus interface that has evolved from the parallel interface ATA.  SATA is preferred over ATA due to various reasons like better performance and less power consumption.

ATA stands for Advanced Technology Attachment. The name has been officially assigned by the American National Standards Institute group X3T10 to refer to Integrated Drive Electronics (IDE). It is a disk drive implementation that evolved from the transistor-transistor logic (TTL) bus interface technology. ATA basically defines a standard interface that enables the one to connect storage peripherals to PC computers. Originally, it catered to only hard drives, but later with the extension known as ATAPI (ATA Packet Interface), other storage peripherals like CD-ROM drives, DVD-ROM drives, etc. were also able to connect. ATA comes in various versions like ATA 1, ATA 2, ATA 3, ATA 4, etc.

It allows the storage peripherals to be directly connected with the motherboards. It is a 16-bit parallel interface which means that 16 bits are transmitted simultaneously down the interface. It can support one or two hard drives. It is important to mention that whenever an item is denoted as a ATA device, it generally indicates a Parallel ATA (PATA) device. ATA devices are also commonly known as IDE, EIDE, Ultra-ATA, Ultra-DMA, ATAPI, PATA, etc. However, these terms refer to some very specific types of items, still they are commonly used interchangeably.

SATA stands for Serial Advanced Technology Attachment. It refers to the next generation computer bus interface that has evolved from the parallel interface ATA. SATA can be viewed as a serialized enhancement and replacement to parallel IDE. Transfer rates for Serial ATA start at 150MB/s. It is the predominant disk interface technology in:

• Desktop PCs
• Entry-level servers
• Entry-level networked storage systems

Comparison between ATA and SATA:

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