Single instruction, multiple data
class of parallel computers in Flynn's taxonomy, with multiple processing elements that perform the same operation on multiple data points simultaneously
Single instruction, multiple data (SIMD) is a type of parallel computing (processing) in Flynn's taxonomy. SIMD describes computers with multiple processing elements that perform the same operation on multiple data points simultaneously. SIMD can be internal (part of the hardware design) and it can be directly accessible through an instruction set architecture (ISA), but it should not be confused with an ISA.
Such machines exploit data level parallelism, but not concurrency: there are simultaneous (parallel) computations, but each unit performs exactly the same instruction at any given moment (just with different data). A simple example is to add many pairs of numbers together, all of the SIMD units are performing an addition, but each one has different pairs of values to add. SIMD is especially applicable to common tasks such as adjusting the contrast in a digital image or adjusting the volume of digital audio. Most modern central processing unit (CPU) designs include SIMD instructions to improve the performance of multimedia use. In recent CPUs, SIMD units are tightly coupled with cache hierarchies and prefetch mechanisms, which minimize latency during large block operations. For instance, AVX-512-enabled processors can prefetch entire cache lines and apply fused multiply-add operations (FMA) in a single SIMD cycle.
Confusion between SIMT and SIMD
SIMD has three different subcategories in Flynn's 1972 Taxonomy, one of which is single instruction, multiple threads (SIMT). SIMT should not be confused with software threads or hardware threads, both of which are task time-sharing (time-slicing).
This brief starts where responsible research should: with the source description of “Single instruction, multiple data” as class of parallel computers in Flynn's taxonomy, with multiple processing elements that perform the same operation on multiple data points simultaneously. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as class of parallel computers in Flynn's taxonomy, with multiple processing elements that perform the same operation on multiple data points simultaneously. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 30, 2026. The linked authority identifier is Q339387. The Library of Congress control number is sh2012002030. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1972.
A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. 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.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Single instruction, multiple data”, its source revision and the description used here.
- Expand the search: follow Single instruction, multiple data primary sources, Single instruction, multiple data archive and Single research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Single instruction, multiple data”?
- Which cited source is closest to the event, object or claim?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “Single instruction, multiple data” 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.