ListId

Listid, often written as ListID or listid, is a term used in computing to denote the unique identifier assigned to a list or collection within a system. Its exact meaning and usage vary by context, but the central idea is to provide a stable reference to a specific list so it can be retrieved, displayed, or associated with other data.

Common contexts

- Email and mailing lists: In email systems, the List-Id header identifies the mailing list that a message belongs to. This helps email clients group messages, present a list name to users, and support threading and filtering by list.

- Data storage and APIs: In databases, data services, or API designs, a listid serves as a key or identifier for a particular list resource. It may be used in URLs or query parameters to fetch the list and its items, manage permissions, or link related objects.

- User interfaces and integrations: Applications may expose listid values in URLs or API calls to enable sharing, bookmarking, or cross-system referencing of specific lists. Access control often hinges on the correct authorization associated with the listid.

Formats and validation

List identifiers are typically strings. Common formats include numeric IDs, alphanumeric tokens, or UUIDs. Validation rules may enforce length limits, character restrictions, case sensitivity, and protection against injection or leakage of sensitive names.

Considerations

Because the term listid can refer to different concepts in different systems, documentation should clearly define its exact meaning, scope, and access rules within a given context. Consistent naming and validation help prevent confusion and security issues.

See also

List-Id header, UUID, GUID, List resource, Identifier.