What is Javascript?

• Clientside vs Serverside
• Everything are Objects
• Weakly typed scripting language
• Non-blocking & Asynchronous

JS frameworks

What makes them unique?

jQuery

• Simple API
• Plugins
• DOM-manipulation

Backbone

• MVC-structure

Angular

• MVC-structure
• Data-binding within client
• Extend HTML with new functionality
• Build an app

Example: admin page with data-binding

Node.js

• Server-side Javascript
• Non-blocking I/O

Meteor

• Data-binding in client(s)
• Sync with the servern (real-time system)

Example: wedding webshop

d3.js

• Data-driven documents (d3)
• Vector graphics
• Transitions / animations

Example: election graphics

Famo.us

• Cool animations
• New way to build and render page
• Build an app, not a document

Pseudo code

Classic programming language Blocking operations

    parse_file(1);
    parse_file(2);
    parse_file(3);
    save_to_db();

Node.js - callbacks

function (fileContent, callback) {
    // Parse the file
    .....
    callback();
}

Node.js

• non-blocking I/O
• Perfect for workers
• 120 sec → 12 sec

Real case: election graphics

Results

• 20 interactions / visit
• 2 million unique visitor / 24h
• 11.7 million page loads / 24h
• 122.000 concurrent users
• ...

Most viewed article at Aftonbladet.se

- ever!