What is LISK?

Lisk is a public blockchain platform that provides decentralized blockchain apps. It was forked from Crypti by Max Kordek and Oliver Beddows in early 2016

History

Lisk started as a fork of Crypti beginning with an ICO (Initial Coin Offering) to decide the initial distribution and raise development funds. The ICO raised 14,000 BTC and, at the time, was the second most successful cryptocurrency crowdfund (later that month, WAVES and The DAO would surpass it). On May 24, 2016, the mainnet for Lisk went live and it became available for trading on major exchanges. Quickly after trading started, Lisk briefly became the second most popular cryptocurrency traded against Bitcoin.

Blockchain Applications

Lisk is on the path to be the first (successful) of its kind as a modular cryptocurrency. The idea behind Lisk is that every Blockchain App is on its own sidechain, separate from the main blockchain. The benefits from this would be solving scalability issues that many cryptocurrencies are facing, such as bitcoin and ethereum, while also allowing for far greater customizations to particular sidechains which could not be done on other platforms. The possibility that sidechains create is vast and can allow for a project coded from scratch to have its own security algorithm separate from what may be securing the Lisk mainchain.

Programming Languages

The Lisk infrastructure is written using NodeJS/JavaScript on the backend and CSS3/HTML5/JavaScript for the frontend.

DPoS Design
Lisk uses the DPoS (Delegated-Proof-of-Stake) algorithm originally created by BitShares. What differentiates it from regular PoS (Proof of Stake) is that only the top 101 delegates (determined by voting weight of voters) are actively forging and securing the network.
Lisk DPoS functions through a series of rounds. Rounds consist of 101 individual blocks. Each of the 101 active delegates are randomly assigned 1 block within the round to forge. A full cycle round takes 17 minutes. If a selected delegate is unable to forge their assigned block, activity from that block moves to the next block in the round.

Block Time

The Lisk network forges blocks in 10s intervals. In the event that a delegate fails to properly forge their assigned block, the transactions move to the next block in the round, causing the block to be extended by 10s. Each subsequent missed block results in a 10s delay for transaction processing and confirmations.
Forging
Lisk utilizes an inflationary forging rewards system which creates new LSK for every successful block. During year 1, the forging rewards are set at 5 LSK per block. Every 3,000,000 blocks (~1 year) forging rewards are reduced by 1 LSK, ending at 1 LSK per block after 5 years. The forging rewards will then stay at 1 LSK per block indefinitely. The Forging Rewards will be equally distributed through all active (top 101) delegates, same as any network fees.
Distinctions from other cryptocurrencies
Lisk is commonly compared to Ethereum and Crypti, so it is important to note their differences.

Differences from Ethereum

Lisk and Ethereum both try to provide a platform for a similar idea: Decentralized Applications (Lisk calls them Blockchain Applications)
• Applications language: Lisk uses Javascript, while Ethereum currently uses Solidity.
• Applications location: Lisk uses sidechains, while Ethereum currently stores it on the main chain.
• Error handling: In Lisk, if your application has an issue it will be contained to only your chain, but require a hard fork to fix. In Ethereum, applications are run in a virtual machine on the main chain so any error should just result in the waste of transaction fees, but be contained to the VM (as long as there is no bug in the VM).
• Lisk uses DPoS, while Ethereum currently uses PoW (they have stated they plan to switch to PoS eventually).
• Applications VM: Ethereum applications are run in the Ethereum Virtual Machine (EVM). Lisk does not have a VM, but it is in development.

Differences from Crypti

Lisk commonly compared to Crypti, because it is a fork of it. However, they have various differences:
• The database has been changed from SQLite to PostgreSQL.
• Completely open source and the whole development procedure is happening in public on GitHub.
• BIP39 enforced for all passphrases
• Development is continuing and active, while Crypti seems to have stopped.