Glossary of Terms

This glossary provides definitions for key terms used throughout this website related to Digital Identity and Self-Sovereign Identity (SSI). Understanding this terminology is helpful for navigating the concepts discussed in pages like What is Digital Identity? and Key Technologies in SSI.

Attribute
A piece of information or data that describes a characteristic of an entity (e.g., name, age, email address).
Authentication
The process of verifying the identity of a user, system, or device. It answers the question, "Are you who you say you are?"
Authorization
The process of granting or denying specific permissions to an authenticated user, system, or device. It answers the question, "Are you allowed to do that?"
Blockchain
A type of Distributed Ledger Technology (DLT) where transactions are recorded in blocks that are cryptographically linked together in a chain. Often used as an anchoring layer for DIDs. For more, see Understanding Blockchain Technology.
Claim
A statement made about a subject, often by an issuer. For example, "Alice is over 18." Verifiable Credentials carry digitally signed claims.
Abstract image representing a network of interconnected terms or ideas.
Key terms form the building blocks of understanding SSI.
Credential
A piece of evidence that attests to a fact or an attribute of a subject. In SSI, these are often Verifiable Credentials.
Cryptography
The use of mathematical techniques to secure communication and information. Includes methods like encryption, digital signatures, and hash functions.
Decentralized Identifier (DID)
A globally unique identifier that does not require a centralized registration authority. DIDs are controlled by their subject and are a core component of SSI. See Key Technologies in SSI.
DID Document
A JSON document associated with a DID that contains metadata about the DID, such as cryptographic public keys and service endpoints, enabling trustworthy interactions.
Digital Footprint
The trail of data an individual leaves behind while interacting online. This includes websites visited, emails sent, and information submitted to online services.
Digital Identity
The online presence and body of information that represents an individual, organization, or device in digital systems. Covered extensively in What is Digital Identity?.
Digital Wallet (Identity Wallet)
A software application that allows users to securely store and manage their DIDs, Verifiable Credentials, and cryptographic keys, enabling them to control and present their identity information.
Distributed Ledger Technology (DLT)
A database that is consensually shared and synchronized across a network spread across multiple sites, institutions, or geographies. Blockchain is a common type of DLT.
Puzzle pieces with icons representing various identity and security concepts.
Understanding each term helps piece together the SSI puzzle.
Holder
In the context of VCs, the entity (usually an individual) that possesses and controls their credentials and presents them to verifiers.
Issuer
An entity that makes claims about a subject and issues Verifiable Credentials to a holder.
Key Management
The handling of cryptographic keys, including their generation, storage, use, and revocation. A critical aspect of SSI security.
Self-Sovereign Identity (SSI)
An model of digital identity that allows individuals to control their own identity information without relying on centralized authorities. Explored in depth on our Exploring SSI page.
Selective Disclosure
The ability for a holder to reveal only specific pieces of information from a Verifiable Credential, rather than the entire credential, to a verifier. This enhances privacy.
Verifiable Credential (VC)
A tamper-evident digital credential containing claims made by an issuer about a subject. VCs are cryptographically signed and can be verified by third parties. See Key Technologies in SSI.
Verifier
An entity that requests and cryptographically checks a Verifiable Credential presented by a holder to confirm the validity of the claims within it.
Zero-Knowledge Proof (ZKP)
A cryptographic method by which one party (the prover) can prove to another party (the verifier) that they know a value x, without conveying any information apart from the fact that they know the value x.

This glossary is a living document and may be updated as the field of digital identity evolves. For a look at how terminology and understanding evolve in other tech domains, consider Exploring Augmented Reality (AR) and Virtual Reality (VR).