JS in 20 minutes

JS in 20 minutes // Smena Station Sri Lanka Edition 2022

Transcript

1. @volyx JS in 20 minutes
2. • Why Javascript? • What is Javascript? • What can you do with it? • Where is Javascript code run? Agenda
3. • Front-end Developer • Back-end Developer • Full-stack Developer Why JS?
4. Why JS?
5. Why JS?
8. JavaScript Engine
9. NodeJS
10. What is IDE?
12. Variables • We use variables to store data temporary • let a = 1; • cannot be reserved word • should be meaningful • cannot start with number (1a) • cannot contain a space or hyper • are case sensitive • let fi rstName = ‘John’; • (const, var) - SOON
13. Primitive Types • let name = ‘Josh’; // String Literal • let age = 30; // Number Literal • let isApproved = true; // Boolean Literal true/false • let fi rstName = unde fi ned; • let color = null;
14. Dynamic Typing let name = ‘Josh’; // String Literal let age = 30; // Number Literal let isApproved = true; // Boolean Literal true/false let fi rstName = unde fi ned; let color = null; typeof name
15. Primitives / Value Types 
 • String • Number • Boolean • unde fi ned • null
16. Reference Types • Object • Array • Function
17. Objects • let p = {a: 1, b: 2}; • dot notation/bracket notation • p.a = 1; • p[‘a’] = 1;
18. Arrays let coolers = [‘color’, ‘red’]; colors[0] = ‘orange’; console.log(colors);
19. Functions function greet() { console.log(‘Hello world!’); }
 
 function square(number) { return number * number; }
20. Thanks! Questions?