DoCid

docID, short for document identifier, is a unique reference assigned to a document within an information system to enable consistent retrieval, linking, and management. A docID is typically independent of a document's storage location, so it remains valid even if the document is moved or renamed. docIDs are used in content management systems, knowledge bases, and digital libraries to identify versions, track history, and support programmatic access through APIs.

Formats vary. Some systems use opaque identifiers such as UUIDs or GUIDs; others use human-readable strings that encode metadata. Common generation approaches include sequential numeric IDs, random UUIDs, or cryptographic hashes of content and metadata. Important properties include uniqueness, persistence, and collision resistance. In distributed environments, universally unique IDs (UUIDs) are popular.

Lifecycle: once assigned, the docID is typically immutable and serves as the primary reference in databases, indexes, and links. Deletions may recycle IDs in some systems, but best practice is to retain IDs for historical integrity by archiving rather than reusing.

docID is used in indexing, caching, permissions, and audit trails; applications embed docIDs in URLs or API calls to fetch the document. It is related to other identifiers but different from URLs, DOIs, or ISBNs; docIDs are usually internal to a system and not guaranteed to be globally resolvable.

Design considerations include balancing readability with privacy, avoiding exposure of sequential IDs in public URLs, and preferring opaque IDs to reduce information leakage. It is also important to ensure persistence and to choose a generation method appropriate to scale and interoperability. See also: unique identifiers, UUID, DOI, and content management best practices.