Paper Wallet

A type of cold storage where private and public keys (and often a QR code) are printed or written on physical paper to prevent hacking and theft.

Peer-to-Peer (P2P)

A peer-to-peer network that distributes computing tasks among many, private computers (decentralized servers), instead of using company computers (centralized servers).

Permissioned Ledger

Similar to a ledger (see above) but designed with restrictions, so that only a select group of people or organizations have permission to access the full features.

PKI (Public Key Infrastructure)

A set of roles, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates and manage public-key encryption.


The Lightning Network concept implemented on the Ethereum blockchain.

Private Blockchain

Only allows authorized entities to operate or participate within the network. E.g., just like a private road has access only for the authorized members.

Private Key

A string of letters and numbers that are used for sending cryptocurrency. The private key should be kept secret because it enables spending with the cryptocurrency wallet.

Proof of Authority (PoA)

A consensus mechanism in a private blockchain which essentially gives one entity (or a specific number of entities) with one particular private key the right to make all of the blocks in the blockchain. This is similar to root certificate authorities used in TLS/HTTPS.

Proof of Capacity (PoC)

Proof of Capacity (POC) is a consensus mechanism used in blockchains that allow the mining devices in the network to use their available hard drive space to decide the mining rights.

Proof of Stake (PoS)

Miners still process and validate transactions, but do so by proving that they have ownership of a certain amount of the asset, rather than by performing energy-intensive computations.

Proof of Work (PoW)

Miners process transactions by using computers to solve complicated mathematical puzzles. They prove that they did this computational work by finding solutions to those puzzles.


A set of rules that dictate how data is exchanged and transmitted.

Public Blockchain

A network on the global internet allowed to participate in all available transactions and participate in the consensus protocol to help determine who gets to add blocks on the chain and maintain the shared ledger. E.g., just like a public road has open access to anyone.

Public Key

A string of letters and numbers that are used to receive cryptocurrency. Works similar to a traditional bank account number and can be shared publicly with others.

Public Key Cryptography

A cryptographic system that uses both a private key and public key to safeguard transactions.