meet it

Give every box a name that tells you what is inside.

Names can use letters, digits, _ and $. They cannot have spaces and cannot start with a digit. Capitals matter, so pet and Pet are two different boxes.

Good names say what is inside. x tells you nothing, but petName tells you everything. Your future self will thank you.

Need more than one word? Squash them together and give each new word a capital letter, like bestFriend. This is called , because the capitals stick up like humps.

let bestFriend: string = "Priya";
console.log("My best friend is " + bestFriend);

TypeScript does not mind what your names mean, but people reading your code do.

guess first

Two boxes, nearly the same name. What shows?

Guess before you run it. Wrong guesses are how you learn, and nothing is marked.

let score: number = 5;
let Score: number = 99;
console.log(score);

your turn

Your turn. Name the boxes.

Choose a camelCase name for each box, like dogName. Use the same two names again in the last line, then press run.

Your code

press run to see what happens

fix it

This name breaks the rules. Can you fix it?

Broken code to fix

press run to see what happens

The error points at line 1. Look closely at the name of the box.
A name cannot have a space in it. TypeScript reads favourite as the name, then gets lost.
Write favouriteColour in camelCase on both lines, then press run.

nailed it

you gave your boxes great names. :D

Names use letters, digits, _ and $, with no spaces.
A name cannot start with a digit, and capitals matter.
Use camelCase names that say what is inside.

new words in your collection

camelCase

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