⛽ What is Gas?
Fee to execute operations on Ethereum

More complexity = more gas

Tips to Reduce Gas Costs:
Store less data on-chain

Use uint256 over smaller types

Use structs efficiently

🔝 Layer 2 Scaling Solutions:
Solution
Type
Benefit
Optimism
Rollup
Reduces gas costs by batching
Arbitrum
Rollup
High throughput & EVM-compatible
Polygon
Sidechain
Fast & cheap, widely used