Ternary operator

statement is true ? run this code : run this code otherwise

const variable2 = variable1  || 'new'; // variable 2 is assigned variable 1 
//unless it doesn't exist, then it's assigned the value 'new'

let x, y, z=3; // assign multiple variables at once

sayHello = name => console.log('Hello', name); // if you have just one parameter
//and no default parameter