Ethereum is a blockchain-based computing platform and operating system whose core innovation is enabling smart contracts. Ethereum's smart contract functionality, and versatile scripting language, have made it the most popular network for creating decentralized applications. What makes Ethereum different from Bitcoin is that its primary purpose is to serve as a general purpose blockchain for creating DApps, and not as a payment network. Ethereum was created by Vitalik Buterin. It was launched in July 2015 and has become one of the most important blockchain platforms in the industry. Ether is the native currency of the Ethereum blockchain and can can be used as a transfer of value, as well as a form of compensation for mining. The Ethereum Virtual Machine (EVM) executes scripts using a network of public nodes. "Gas" is used as an internal transaction pricing mechanism that decides how resources are used on the network.

NEM is a cryptocurrency and blockchain platform that allows multiple ledgers on the same blockchain. NEM Smart Assets are used to create mosaics for any asset. Transaction fees are paid with NEM's native currency, XEM. NEM originally began as a community-oriented cryptocurrency that was built from the ground up in the Java programming language.
NEM's goal is to achieve widespread distribution through improved scale and speed. It pioneered several blockchain features such as its proof-of-importance (POI) consensus algorithm, encrypted messaging, a unique reputation system, and multi-signature accounts.
NEM is also developing a commercial blocckahin called Mijin, that is currently being tested by several companies and financial institutions.
In early 2018, approximately $400 million worth of XEM were stolen from a Japanese exchange called Coincheck, that was the victim of huge hack. The exchange failed to implement proper security for this coin protocol, and the hackers only stole XEM coins as a result. Instead of creating a fork to deal with this issue, NEM set up an automated tagging system that flagged these funds. NEM then stopped tracking these stolen coins

PascalCoin is the first blockchain that can be deleted, and reduces the dependency of the entire blockchain history to verify transactions. It is a Proof-of-Work (PoW) cryptocurrency that places a strong emphasis on achieving the same level of scalability as credit card networks such as VISA. Pascal's architecture is based on an innovative cryptographic structure called the SafeBox. It facilitates faster transactions by storing account balances separately from the blockchain. The SafeBox only uses the last 100 blocks on the chain to update transaction history. This allows the network nodes to synchronize much faster while preserving the security of the blockchain, and reducing the computing resources needed to maintain it.
PascalCoin also enables simplified account naming to make it easier to transfer funds.