EOS is a blockchain development platform created by Block.one. Its goal is to become an all purpose operating system for blokchain applications. EOS allows developers to make underlying blockchains and create decentralized application more easily. It was designed from the ground up, to be more scalable and faster than other blockchain platforms. This allows for greater throughput, with more transactions per second, and much lower transaction fees. EOS tokens serve as the native currency. The network has a Delegated Proof-of-Stake (dPoS) consensus mechanism. Transactions are verified by 21 block producers that are chosen through a voting process that is designed to encourage community participation.

GAS is the token that is used to pay for transaction fees on the NEO network. The NEO platform uses two different tokens; GAS are used to fuel the network and give holders the right to use the NEO blockchain. Similar to Ether on the Ethereum network. Although it's possible to buy GAS on some exchanges, NEO token holders automatically generate GAS as the blockchain increases in size. 8 GAS are distributed for every 100 million NEO in circulation.

.

BitcoinDark is a fork of Bitcoin with a poorly defined purpose and use case. BitcoinDark is based on the InstantDEX protocol, a decentralized exchange for BitcoinDark and other cryptocurrencies supported by the project. The platform is also supposed to include a Pegged Asset Exchange (PAX) to allow users to buy and sell pegged assets – including fiat currencies, commodities, ETFs, and stocks.
BitcoinDark is a Proof-of-Stake (PoS) currency that has gained a significant market cap, but the project has failed to show how its vision will be implemented or how it will add value compared to other blockchain projects.