A solid-state drive (SSD) is a data storage device that uses a processor and NAND flash memory chips to deliver high read/write speeds. It's typically more expensive than an HDD, but the performance and reliability advantages make it an attractive option for laptops and tablets, digital cameras and smartphones. SSDs can also be used to replace or supplement traditional hard disk drives in desktop computers, servers and external enclosures.

The key advantage of SSDs over HDDs is that they don't have moving parts. This makes them less prone to physical shock and more resistant to operating in extreme temperatures. SSDs also tend to run silently, which reduces noise and thermal throttling in systems that must balance performance with battery life.

Because the drive has no moving parts, it also requires less power than a spinning hard disk. That's a big benefit for mobile devices, where reducing heat and power consumption is essential to maximize battery life.

SSDs use a controller to manage the NAND flash memory chips and optimize performance for sequential and random data requests. The controller is also responsible for storing, restoring and caching data. The performance of an SSD depends on the number of flash chips in the drive and its capacity, which is determined by the amount of data that can be written to each chip over its lifetime.

In addition to the NAND memory, SSDs use other components including a circuit board and an enclosure. They can be connected to a motherboard using either a traditional HDD interface or newer form factors like mSATA, U.2, NF1/M.2/NGSFF or NVME over PCIe.SSD drive