Free course · Lesson 1 of 5
JavaScript Fundamentals & Setup
In this lesson you will
- Run JavaScript in the browser console
- Store values with let and const and build text with template literals
JavaScript is the only language that runs natively in every web browser, which makes it the
foundation of interactive websites — and, via Node.js, of servers too. Modern JavaScript uses
let and const for variables instead of the older var.
constfor values that never get reassigned;letfor values that do.- Core types:
string,number,boolean,undefined,null. - Template literals (
`Hello ${name}`) build strings without messy concatenation. - A script runs in the browser via a
<script>tag, or on the server withnode file.js.
💡 Practical Skill: Install VS Code and open its built-in terminal. Open Chrome DevTools (F12) and use the Console tab to run and test small pieces of JavaScript instantly.
const name = "Grace";let age = 22;const city = "Juba"; console.log(`${name} is ${age} years old and lives in ${city}.`); age = age + 1;console.log(`Next year, ${name} will be ${age}.`);
Practice exercise
In the browser console, store the price of three items in SSP in constants and print a sentence with their total using a template literal.
Key takeaways
- Use const by default and let when a value must change
- Template literals with ${} build readable text
- Values from forms are strings — convert them with Number()
Free self-study lesson — no certificate. For the full instructor-led program, see registration options.