HED specification

Welcome to the official specification for Hierarchical Event Descriptors (HED), a system for annotating events and experimental structure using controlled vocabularies. The HED ecosystem includes:

  • Vocabularies - Standardized terms organized in hierarchical schemas

  • Annotation tools - Software for creating and validating HED annotations

  • Analysis tools - Methods for searching and analyzing HED-annotated data

  • Community schemas - Domain-specific extensions to the base vocabulary

Core specification

The core chapters provide the foundation for understanding and using HED.

Advanced topics

These chapters cover specialized aspects of the HED ecosystem.

Reference materials

Additional technical reference and validation information.

Indices and tables