If you've owned a desktop PC or laptop in the past decade and a half, you can guarantee that you have owned a SATA (Serial ATA) compatible piece of hardware. Whether it was a hard drive (HDD), a solid-state drive (SSD), or an optical drive -- almost all of them, until very recently, used SATA. What is SATA? In short, it's how almost everything storage related connects to your motherboard.
That's not always the case, as there are some newer standards available for high-speed drives. But alongside PCIe and NVMe, SATA is still a major player, especially when it comes to larger-sized HDDs and SSDs.
Although there are a myriad of computer products which are designated as "SATA" devices, the reason they call themselves that is because they use the SATA interface. That is, the cables that connect them to the rest of the PC, are connected to a SATA port on the drive and another on the motherboard.
Although SATA connectors are typically described as a singular port or connector, SATA actually encompasses two: the data connector and the power connector. The former is the short, "L" shaped, seven-pin connector, while the latter is the longer, 15-pin connector -- the taller "L" of the two.
Both connectors tend to be reversed on the drives they allow connections for, with the bases of their respective "L" facing one another. Beyond length, they can be told apart by the cables that connect to them. Where the SATA data cable is almost always made up of solid plastic which extends into a flat, single band cable, the SATA power connector will extend from its head to multiple, thin, rounded cables of different colors.
Both cables are required for SATA devices to work and both do different jobs. The data cable provides the high-speed connection to the rest of the computer, transferring information back and forth as requested, while the power cable is what gives the drive the electricity to run in the first place.
Although most PCs in recent years have used SATA devices, there are a few different types that are worth noting. SATA was first introduced in 2000, replacing the aged PATA ribbon cables. It was revised in 2003 and again in 2004, and 2008, bringing SATA to version three -- commonly referred to as SATA III, or 3.0. These standards increased speed and added additional features to allow for faster and more reliable storage drives, but didn't change the physical look of the SATA connector itself. SATA III is the most common SATA interface used today.
There have been a few alternative SATA interfaces over the years though. mSATA for laptop drives debuted in 2011. The latest generation of that technology is the M.2 standard, though the fastest of those drives have moved beyond the mSATA interface and now take advantage of PCIexpress ports for greater performance.
SATA Express allowed for cross-compatibility with SATA III and PCIexpress drives, but wasn't a popular choice, while eSATA offered SATA-like speeds for external drives. Today, most high-speed external drives use USB 3.0 connections, commonly with the Type-C standard of connector.
Although in 2008 SATA reached a near complete saturation of the PC market with as much as 99 percent of all drives utilizing the standard, that's not necessarily the case today. Where many smaller laptops and tablets will use built-in flash memory for their main storage, higher-end desktop and laptops will instead now use faster standards like PCIexpress to deliver greater performance.
SATA is still an important connection standard, especially for larger hard drives and SSDs in the multi-terabyte range, but for those opting for performance, newer M.2 and NVMe drives are the go-to choice. They are more expensive, but plugging into a PCIexpress slot instead of a SATA port gives them a connection that isn't constrained by the limits of SATA cabling and allows drives to operate at far-faster data rates. For some, as fast as gigabytes of data per second, compared with the hard SATA III limit of 600MBps.