Now let’s define a few terms…

According to the Sovrin Foundation Glossary v3 a claim is an assertion about an Attribute of a Subject. Examples of a Claim include date of birth, height, government ID number, or postal address—all of which are possible Attributes of an Individual.
A Credential is comprised of a set of Claims and is a digital assertion made by an Entity about itself or another Entity. Credentials are a subset of Identity Data and must be based on a Credential Definition. Examples of Credentials include college transcripts, driver licenses, health insurance cards, and building permits.
Credential – Agent
Once issued, a Credential is typically stored by an Agent.
Credential – Holder
The Entity holding the issued Credential.
Credential – Issuer
The Entity creating and issuing the Credential.
Credential – Relying Party
The Entity to whom a Credential is presented.
Credential – Subject
The Entity described by the Claims is called the Subject of the Credential.
Credential – Verifier
The Entity to whom a Credential is presented for verification.
De-centralized Key Management System (DKMS)
Public key infrastructure based on decentralized identifiers and identity records (for example, DID documents) containing verifiable public key descriptions.
Digital Identity
According to Wikipedia digital identity is information on an entity used by computer systems to represent an external agent. That agent may be a person, organisation, application, or device. ISO/IEC 24760-1 defines identity as “set of attributes related to an entity”.
Digital Wallet
A software module, and optionally an associated hardware module, for securely storing and accessing Private Keys, Link Secrets, other sensitive cryptographic key material, and other Private Data used by an Entity. A Wallet [Wallet Storage] is accessed by an Agent. In Sovrin infrastructure, Wallets [Wallet Storage] implement the emerging DKMS standards for interoperable decentralised cryptographic key management. Darrell O’Donnell’s 2019 paper entitled The Current and Future State of Digital Wallets provides a guide to help understand where the Digital Wallet market is and where it is heading for business and personal use.
Distributed Ledger Technology (DLT) or Blockchain
A distributed database in which the various nodes use a consensus protocol to maintain a shared ledger in which each transaction is cryptographically signed and chained to the previous transaction.
Personal (Online) Data Store (POD)
A personal data store, vault or data locker is a service that lets an individual store, manage and deploy their personal data in a highly secure and structured way. PODs are like secure USB sticks for the Web that can be accessed from anywhere. When others are given access to parts of the POD, they can react to the the content but the data owner decides which things can be accessed by applications and people. A Personal Data Store is NOT a Digital Wallet, it is more like a personal, domestic filing cabinet that stores persoanl data. Solid and Mydex are just two examples of personal data stores.
Self-sovereign Identity (SSI)
Lifetime portable identity for any person, organisation, or thing that does not depend on any centralised authority and cannot be taken away. Also describes the digital movement that recognises an individual should own and control their identity without the intervening administrative authorities. Christopher Allen’s excellent post from 2016 provides another useful overview of the subject.
Trust Framework
A generic term often used to describe a legally enforceable set of specifications, rules, and agreements that govern a multi-party system established for a common purpose, designed for conducting specific types of transactions among a community of participants, and bound by a common set of requirements.
Web of Trust
Phil Zimmerman originated the phrase “Web of Trust” in PGP 2.0 (1992), however, his ‘Web’ had a very limited meaning, focused on peer validation of public keys.
Verifiable Credentials
A digital attestation of one Identity Owner about another, also called Attestations or Claims.
A way to uniquely identify a person, company, organisation, or other agent using a URI, defined by the W3C WebID 1.0 specification.
Enables secure, efficient and maximally user friendly authentication on the Web by authentication onto any site by simply choosing one of the certificates proposed to them by their browser. These certificates can be created by any Web Site for their users.

As a good primer on the subject I highly recommend Sovrin’s White Paper entitled “Sovrin: A Protocol and Token for Self-Sovereign Identity and Decentralised Trust“.