Editing SD (section)

==Science and technology==
===Astronomy===
* [[Subdwarf]], a class of star
* Surface detector, of cosmic rays at the [[Pierre Auger Observatory#Surface detector (SD)|Pierre Auger Observatory]] 

===Electronics and computing===
* [[SD card]] (Secure Digital), a flash memory card format
* [[Software Distributor]], an HP-UX system
* [[Standard-definition television]]
* [[Super Density Disc]], an optical disc format
* [[Stable Diffusion]], a text-to-image generator

===Mathematics===
* [[sd (elliptic function)]], one of Jacobi's elliptic functions
* [[Standard deviation]] (SD), a statistical measure of variation

===Medicine===
* [[Spasmodic dysphonia]], a voice disorder
* Stable disease, a [[RECIST]] chemotherapy outcome

=== Other uses in science and technology ===
* [[Service design]], holistic design of service experience
* [[Spiral Dynamics]], a model of individual and societal development
* ''[[Storm Data]]'', a US meteorological journal
* [[System dynamics]], of nonlinear systems