Until now, we’ve gone through the following -

1. What are blockchains, how do they work under the hood
2. Public and Private keys, how you can use them to sign transactions that miners use to verify and credit/debit balances

In today’s class, we’ll understand about one of the biggest use-case that blockchains like Solana/ETH solve for - Programs/Smart contracts.

Programs/Smart contracts

ETH was one of the first blockchains to introduce the concept of decentralized state / programs. These are popularly known as smart contracts on the ETH blockchain.

• Here is a simple ETH smart contract
• Here is a simple Node.js HTTP server that does something similar

HTTP Servers are deployed on cloud providers like GCP, Azure

Smart contracts/programs are deployed on the blockchain

The way solana programs work is significantly different from other blockchains. Lets understand how.