Key Terms in Crypto

Rufus Wright
3 min readAug 12, 2019

Terms like Token, Coin, cryptocurrency, ledger, and blockchain are thrown around a lot, and I have found an enormous amount of confusion surrounding these terms. Following are some key definitions of various Crypto related terms which have been fairly well agreed upon within the industry. All of these definitions are based on my observations and experiences working in this space since 2015. This is an evolving industry and things are always changing, so I will try to keep this post updated as the landscape evolves. As always please feel free to post replies and I am always happy to hear about how or why anyone thinks I am wrong.


A Blockchain is a continuously growing list of records, called blocks, which are linked and secured using cryptography. Each block contains signed transaction data as well as the hash-function of another block thus forming a chain of such blocks. Together these blocks form a Ledger of all the accounts and transactions that have taken place on the Blockchain.


The Ledger is the term used to describe the current and previous states of a Blockchain. The Ledger is the basis for ownership of Crypto-Assets on a Blockchain and contains all the data of who owns what within the system. All Crypto-Assets use cryptographic public/private key pairs to sign transactions between accounts located on such a Ledger in order to transfer ownership of the Crypto-Assets from one account to another.

Consensus Protocol

This is the governing system that a given Blockchain and Ledger uses to verify, authenticate, and secure transactions. While many Crypto-Assets may use the same consensus mechanism no two Crypto-Assets will share both the exact same Ledger and Consensus Protocol.


This is a very broad term that I have seen used recently and I really like. This term broadly references any access to and/or ownership of the secret (private) key used to cryptographically sign transactions on a cryptographically secure Ledger of some sort. Personally I think that 99% of the time this is a better term to use than cryptocurrency, as it can be used to refer to any of the below mentioned assets and doesn’t carry with it the baggage and misgivings of the term “currency”.


Coins are first layer, independent, protocol-level, crypto-assets. This means that it is not…