A solid-state drive (SSD) is a new generation of storage device used in computers. SSDs replace traditional mechanical hard disks by using flash-based memory, which is significantly faster. Older hard-disk storage technologies run slower, which often makes your computer run slower than it should.
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An M. 2 SSD is a solid-state drive (SSD) that conforms to a computer industry specification and is used in internally mounted storage expansion cards of a small form factor. M. 2 SSDs are designed to enable high-performance storage in thin, power-constrained devices, such as ultrabook and tablet computers