typescript · level 1 · unit 1 · lesson 1
- meet it
- guess first
- your turn
- fix it
- nailed it
Tap a green word if you get lost.
meet it
is a list of instructions for a computer.
Code is instructions written down for a computer. A set of instructions that does one job, like a recipe for toast, is called a . The computer follows it exactly, from the top line down.
We will write our code in . It is JavaScript, the language that makes web pages work, with labels added. The labels help TypeScript catch many mistakes before your code even starts.
When you a program, the computer starts following it. It never guesses what you meant. It does what you wrote.
console.log("Hello!");Press run on this one-line program and the computer says Hello! back to you.
guess first
Spot the typo. What will the computer show?
Guess before you run it. Wrong guesses are how you learn, and nothing is marked.
console.log("Happy brithday, Gran!");your turn
Your turn. Teach the computer a dance.
Make up a dance move and type it between the quotes on line 2. Then press run and watch the steps appear in order.
fix it
Shoes before socks? Can you fix it?
- The computer runs the lines from top to bottom. Which one happens first here?
- Shoes first, then socks? Ouch. The two lines are in the wrong order.
- Swap the two lines so the socks line is on top, then press run.
nailed it
you wrote and ran your first program. :D
- Code is a list of instructions for a computer.
- A program runs from the top line down.
- TypeScript looks for mistakes before your code runs.
new words in your collection
- code
- program
- TypeScript
- run
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