_Follow along with this video:_ --- ### An Introduction to Chisel `Chisel` is one of the 4 components of Foundry alongside `forge`, `cast` and `anvil`. It's a tool that allows users to quickly test the behavior of Solidity code on a local (anvil) or forked network. Usually, when you want to test a small Solidity code snippet you go to Remix. But why do that when you have what you need right in the terminal of your Foundry project. Type `chisel` in your terminal and press Enter. This opens up a shell that awaits your next command. Call `!help` to find out more about what commands are available. Basically, you can simply write solidity in the shell then play around and see how it behaves. For example: 1. Type `uint256 cat = 1`; 2. Type cat; ``` ➜ cat Type: uint256 ├ Hex: 0x0000000000000000000000000000000000000000000000000000000000000001 ├ Hex (full word): 0x0000000000000000000000000000000000000000000000000000000000000001 └ Decimal: 1 ➜ ``` 3. Type `uint256 dog = 2;` 4. Type `cat + dog` ``` Type: uint256 ├ Hex: 0x0000000000000000000000000000000000000000000000000000000000000003 ├ Hex (full word): 0x0000000000000000000000000000000000000000000000000000000000000003 └ Decimal: 3 ➜ ``` 5. Type `uint256 frog = 10;` 6. Type `require(frog > cat);` - If nothing happens it means it passed, now try it the other way 7. Type `require(cat > frog);` ``` ➜ require(frog > cat); ➜ require(cat > frog); Traces: [197] 0xBd770416a3345F91E4B34576cb804a576fa48EB1::run() └─ ← [Revert] EvmError: Revert ⚒️ Chisel Error: Failed to execute REPL contract! ➜ ``` It reverts! Press `Ctrl + C` twice to exit and return to your normal terminal. To find more about other Chisel functionality, please click [here](https://book.getfoundry.sh/reference/chisel/).