[3] SATA was announced in 2000[4][5] in order to provide several advantages over the earlier PATA interface such as reduced cable size and cost (seven conductors instead of 40 or 80), native hot swapping, faster data transfer through higher signaling rates, and more efficient transfer through an (optional) I/O queuing protocol.

The SATA-IO group collaboratively creates, reviews, ratifies, and publishes the interoperability specifications, the test cases and plugfests.

[22] The SATA 3.0 specification contains the following changes: In general, the enhancements are aimed at improving quality of service for video streaming and high-priority interrupts.

SATA cables can have lengths up to 1 meter (3.3 ft), and connect one motherboard socket to one hard drive.

Thus, SATA connectors and cables are easier to fit in closed spaces and reduce obstructions to air cooling.

Some cables even include a locking feature, whereby a small (usually metal) spring holds the plug in the socket.

The use of fully shielded, dual coax conductors, with multiple ground connections, for each differential pair[49] improves isolation between the channels and reduces the chances of lost data in difficult electrical environments.

SATA specifies a different power connector than the four-pin Molex connector used on Parallel ATA (PATA) devices (and earlier small storage devices, going back to ST-506 hard disk drives and even to floppy disk drives that predated the IBM PC).

Some low-level drive features, such as S.M.A.R.T., may not operate through some USB[62] or FireWire or USB+FireWire bridges; eSATA does not suffer from these issues provided that the controller manufacturer (and its drivers) presents eSATA drives as ATA devices, rather than as SCSI devices, as has been common with Silicon Image, JMicron, and Nvidia nForce drivers for Windows Vista.

With passive adapters, the maximum cable length is reduced to 1 meter (3.3 ft) due to the absence of compliant eSATA signal-levels.

[67] Both SATA traffic and device power are integrated in a single cable, as is the case with USB but not eSATA.

Mini-SATA (abbreviated as mSATA), which is distinct from the micro connector,[59] was announced by the Serial ATA International Organization on September 21, 2009.

[69] Applications include netbooks, laptops and other devices that require a solid-state drive in a small footprint.

[71] Slim 2.5-inch SATA devices, 5 mm (0.20 inches) in height, use the twenty-pin SFF-8784 edge connector to save space.

By combining the data signals and power lines into a slim connector that effectively enables direct connection to the device's printed circuit board (PCB) without additional space-consuming connectors, SFF-8784 allows further internal layout compaction for portable devices such as ultrabooks.

[77] As M.2 form factor, described below, achieved much larger popularity, SATA Express is considered as a failed standard and dedicated ports quickly disappeared from motherboards.

Having a smaller and more flexible physical specification, together with more advanced features, the M.2 is more suitable for solid-state storage applications in general, especially when used in small devices such as ultrabooks or tablets.

[78] A M.2 SSD is "keyed" to prevent insertion of a card connector (male) to an incompatible socket (female) on the host.

Essentially, the M.2 standard is a small form factor implementation of the SATA Express interface, with the addition of an internal USB 3.0 port.

Like M.2, it carries a PCI Express electrical signal, however U.2 uses a PCIe 3.0 ×4 link providing a higher bandwidth of 32 Gbit/s in each direction.

In order to provide maximum backward compatibility the U.2 connector also supports SATA and multi-path SAS.

Modern[update] PC systems have SATA controllers built into the motherboard, typically featuring two to eight ports.

Additional ports can be installed through add-in SATA host adapters (available in variety of bus-interfaces: USB, PCI, PCIe).

At the hardware interface level, SATA and PATA (Parallel AT Attachment) devices are completely incompatible: they cannot be interconnected without an adapter.

The common heritage of the ATA command set has enabled the proliferation of low-cost PATA to SATA bridge chips.

The market has produced powered enclosures for both PATA and SATA drives that interface to the PC through USB, Firewire or eSATA, with the restrictions noted above.

This can cause data corruption in operating systems that do not specifically test for this condition and limit the disk transfer speed.

Parallel SCSI uses a more complex bus than SATA, usually resulting in higher manufacturing costs.

SCSI, SAS[citation needed], and fibre-channel (FC) drives are more expensive than SATA, so they are used in servers and disk arrays where the better performance justifies the additional cost.

Note that, in general, the failure rate of a disk drive is related to the quality of its heads, platters and supporting manufacturing processes, not to its interface.