H1ID

H1ID is a label used in various technical contexts to refer to a unique identifier associated with a level-1 heading or with a primary header in data structures. There is no single formal specification for H1ID, and its meaning is context-dependent and not standardized across industries.

In web development, H1ID often describes the value assigned to the id attribute of an h1 element. The id creates an anchor for linking, styling, or scripting, and since id values must be unique within a document, the H1ID typically identifies a single heading in the page's DOM.

In data models and APIs, H1ID may appear as a field name representing the identifier of a record or entity. For example, a JSON object describing a document might include "H1ID": "abc123" as a way to store the primary key or slug. The exact datatype and constraints depend on the schema, and the field name is chosen by project conventions.

In documentation and codebases, teams might adopt H1ID as part of a naming convention to denote the header identifier or the primary key for a section. Because it is not part of HTML or database standards, its use should be documented within a project to avoid ambiguity.

See also: id attribute, header element, unique identifier, naming conventions.