Introduction to JavaScript
JavaScript is a language that makes websites move and talk back.
HTML builds the page. CSS paints the page. JavaScript decides what happens when you click, type, or wait.
Think of a toy car. HTML is the body. CSS is the paint. JavaScript is the remote that makes it drive.
What JavaScript is
Where it runs
Why people learn it
Your first tiny program
What JavaScript does
It listens for clicks, forms, and keys.
It can show messages, hide boxes, and load new data.
Without it, many pages would just sit still like a poster.
Where it runs
It runs inside your web browser.
You do not need a special machine to start.
Open a page, and the browser can run the JavaScript for you.
Why learn it
Almost every website uses some JavaScript.
It helps you build games, apps, and tools.
Many other tools grow from the same ideas.
Buttons that do things
Forms that check your answers
Pages that update without a full reload
How this course works
We go one small idea at a time.
You will see plain words, then a short example.
Try the code. Break it. Fix it. That is how you learn.
Tip: Use the Try it button under code samples. Run the code. Change one word. Run it again.
Test yourself
Three quick questions made just for this lesson. Earn 10 XP per correct answer.