SSD vs. HDD: Technology and Lifespan

hardware
English

SSD vs. HDD: Technology and Lifespan

Solid-state drives (SSD) and classic hard drives (HDD) differ fundamentally in technology, speed and lifespan.

Technology

An HDD writes to rotating magnetic platters — mechanical, fragile, but cheap per terabyte. An SSD stores data in NAND flash cells — no moving parts, instant access.

Lifespan: TBW

SSDs have a limited write capacity, expressed as TBW (Terabytes Written). For normal desktop use (20-40 GB/day), a 500 GB SSD with 300 TBW lasts many years. Enterprise SSDs last much longer.

When to choose what

SSD: operating system, applications, databases, VM storage.
HDD: large media archives, backups, cold storage.
Hybrid: small SSD as cache + large HDD for bulk.

NVMe vs. SATA

NVMe uses PCIe directly and reaches 3,000-7,000 MB/s. SATA SSDs are capped at ~550 MB/s. For servers and workstations: NVMe.