SRd

SRD is an acronym that can refer to several concepts, depending on the field. The most widely recognized meaning in popular culture is the System Reference Document, a legally shareable subset of game rules used in tabletop role-playing games such as Dungeons & Dragons. The SRD is designed to enable third-party publishers to create compatible content while respecting the ownership and license terms of the rights holder. It typically includes core mechanics, creature statistics, spells, equipment, and basic rules text, but excludes proprietary art and extensive flavor material. SRDs are published for particular editions and are updated to reflect rule changes and licensing terms. In practice, publishers and designers cite the SRD to ensure compatibility with the base game’s framework.

Other uses of the acronym exist in science and software. Standard Reference Data refers to curated collections of reference data for physical constants, chemical properties, and related measurements, maintained by national and international standards organizations such as NIST. These data sets serve as benchmarks for research, engineering, and quality control. In software engineering, SRD can occasionally denote a Software Requirements Document or Description, though the more common term for a formal requirements artifact is Software Requirements Specification (SRS).

In sum, SRD most often points to a System Reference Document in gaming contexts, but the acronym also appears in science and software with different, domain-specific meanings. Disambiguation typically relies on context.