Chapter 1 — Variables

New concepts: let, const, var, string, number, boolean, typeof

Open the browser Console (F12 → Console) to see output from console.log().

Exercises

1. Declare a let variable 'myName' with your name — display it
2. Declare a const 'TAX_RATE' = 0.20 — try reassigning it and read the error
3. Explore typeof: check the type of a string, number, boolean, null, undefined
4. Compute: annual salary from monthly, round to 2 decimals — display both