Reactive Programming

Most programming languages or techniques nowadays are sequential. When executing a statement c = a + b, c is the result of the addition of the current values of a and b. If either one of those variables change their value, c is not changed.

var a = 5;
var b = 10;
var c = a + b;
console.log(c); // logs 15
a = 20;
console.log(c); // still logs 15