Often people casually just mention Hyperledger while they actually mean Hyperledger Fabric. To be specific Hyperledger Fabric is a blockchain framework listed as part of Hyperledger community projects hosted by The Linux Foundation.
Using a modular architecture Hyperledger Fabric provides a platform for distributed ledger solutions. It is scalable, supports confidentiality, flexibility and suppleness.
Lets go through all the terminologies or components under the hood of Hyperledger Fabric.
Shared Ledger
Each participant holds a copy of the ledger specific to their Hyperledger Fabric network. It is a combination of the transaction log history and the world state database
World State
It is basically the database of the ledger. It details out the state of the ledger at a given point in time.
Transaction Log
It records all transactions performed on the blockchain platform which led to reach to the current result of the world state. It holds the complete history for the world state
Chaincode
Smart contracts of Hyperledger Fabric are called Chaincode. It is basically a program written on Go language. Support for Java and other languages are expected in future. It helps to manage the ledger state based on the transactions submitted
Asset
In Hyperledger Fabric using a collection of key-value pairs Asset is represented. They can be tangible (Car, Mobile etc.) as well as intangible (any contracts).
Channel
Ledgers exists on scope of channels. All participants of a specific channel can access the ledgers specific to that channel. When a subset of participants want to share something among themselves only then a channel is created specific to them
Consensus
To provide guaranteed ordering of transactions and to validate the block of transactions within network of nodes a consensus mechanism is required.
Kafka
It is the consensus mechanism provided by Fabric. It is a permissioned voting based ordering service. Based on it a leader performs ordering
Endorsement
It is the policy by which the participants endorse a transaction
Endorser
The peer which endorses a newly submitted transaction is called the endorser
Ordering
It is the process to accept endorsed transactions and create the order in which it will be stored to the ledger
Orderer
The peer which plays the role to perform ordering service as listed above is called Orderer
Validation
It is the process of accepting ordered transactions and validate the results which includes checking the endorsement as well
Peer
Every participant in Fabric is actually a peer or node. A peer plays multiple roles like as an endorsing peer and committing peer. Orderer is also a peer having a fixed role perform ordering service as listed above
Organization
An Organizations consists of multiple peers. Each organization has its own Centralized Authority
Membership Service Provider (MSP)
MSP plays the role to issue certificates and validate user authentication. It uses cryptographic mechanisms to provide this service. Fabric blockchain supports one or more MSPs
Hope this gives you a basic idea of the various terminologies present under the hood of Hyperledger Fabric and their significance.