{
  "slug": "ssd",
  "term": "Solid-state drive (SSD)",
  "aliases": [
    "solid-state storage"
  ],
  "definition": "A non-volatile storage device built from flash memory or other solid-state media with no moving parts.",
  "note": "An SSD persists data in non-volatile semiconductor memory—almost always NAND flash—behind a controller that maps logical blocks to physical pages, runs wear leveling and garbage collection, and presents a block or NVMe namespace interface. There are no seeking heads: latency and IOPS come from parallel flash channels and the host protocol (SATA, SAS, or NVMe/PCIe). Cell type (SLC/MLC/TLC/QLC), over-provisioning, and power-loss protection differentiate client vs enterprise SKUs more than the generic “SSD” label. Hosts should issue TRIM/deallocate so the controller can reclaim invalidated pages and limit write amplification. SSDs dominate boot, hot, and latency-sensitive tiers; HDDs still win bulk cold capacity.",
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "related": [
    "nand-flash",
    "nvme",
    "sata",
    "enterprise-ssd",
    "consumer-ssd",
    "ftl"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": {
    "date": "2007",
    "citationIds": [
      "c1"
    ]
  },
  "lastSeen": null,
  "citations": [
    {
      "id": "c1",
      "title": "Solid-state drive",
      "url": "https://en.wikipedia.org/wiki/Solid-state_drive",
      "accessed": "2026-03-26"
    },
    {
      "id": "n2",
      "title": "NVM Express — overview (SSD host interface for PCIe NVM)",
      "url": "https://nvmexpress.org/wp-content/uploads/NVMe_Overview.pdf",
      "accessed": "2026-10-07"
    },
    {
      "id": "n3",
      "title": "SNIA — NVMe, SAS, and SATA SSD endurance white paper",
      "url": "https://www.snia.org/sites/default/files/SSSI/NVMe_SAS_SATA_Endurance_White_Paper.pdf",
      "accessed": "2026-10-07"
    },
    {
      "id": "n4",
      "title": "JEDEC — JESD218 solid-state drive requirements and endurance test method (overview page)",
      "url": "https://www.jedec.org/standards-documents/docs/jesd218b01",
      "accessed": "2026-10-07"
    }
  ]
}