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SD card

removable memory storage for portable devices

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 18, 2026
Entity authorityQ466977 ↗
Source-derived summary

The SD card is a proprietary, non-volatile, flash memory card format developed by the SD Association (SDA). They come in three physical forms: the full-size SD, the smaller miniSD (now obsolete), and the smallest, microSD. Owing to their compact form factor, SD cards have been widely adopted in a variety of portable consumer electronics, including digital cameras, camcorders, video game consoles, mobile phones, action cameras, and camera drones.

The format was introduced in August 1999 as Secure Digital by SanDisk, Panasonic (then known as Matsushita), and Kioxia (then part of Toshiba). It was designed as a successor to the MultiMediaCard (MMC) format, introducing several enhancements including a digital rights management (DRM) feature, a more durable physical casing, and a mechanical write-protect switch. These improvements, combined with strong industry support, contributed to its widespread adoption.

To manage licensing and intellectual property rights, the founding companies established SD-3C, LLC. In January 2000, they also formed the SD Association, a non-profit organization responsible for developing the SD specifications and promoting the format. As of 2023, the SDA includes approximately 1000 member companies. The association uses trademarked logos owned by SD-3C to enforce compliance with official standards and to indicate product compatibility.

History

Origins and standardization

In 1994, SanDisk introduced the CompactFlash (CF) format, one of the first successful flash memory card types. CF outpaced several competing early formats, including the Miniature Card and SmartMedia.

Editorial summary

This brief starts where responsible research should: with the source description of “SD card” as removable memory storage for portable devices. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA dependable orientation record for establishing vocabulary, names and a first evidence trail. The current lead gives the account dated anchors—1999, 2000, 2023, 1000—that can be checked directly. The selected authority fields contribute no independent date. The account is most persuasive where card, removable and memory can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as removable memory storage for portable devices. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 18, 2026. The linked authority identifier is Q466977. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1999, 2000, 2023 and 1000.

Critical limits

The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “SD card”, its source revision and the description used here.
  2. Expand the search: follow SD card primary sources, SD card archive and card research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “SD card”?
  2. Which cited source is closest to the event, object or claim?
  3. What terminology or title could unlock a more precise catalogue search?
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Source & attribution

This entry incorporates text from “SD card” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.