The 'window' is the global object in JavaScript. But, only on the browser, this doesn't apply in server-side Node.js.
If you're running these examples in the terminal using node, this won't work. Run in your favorite browsers dev tools!
// Declare global variables on the window explicitly
window.myName = 'Eric'
console.log(window.myName) // => Eric
// Variables are implicity added without the window keyword
myName = 'Ted'
console.log(window.myName) // => Eric
// any var declared without var, let or const
// is automatically a global var
function newScope() {
function evenDeeperScope() {
windowVar = "I'm on the window"
}
evenDeeperScope()
}
newScope()
console.log(window.windowVar) // => I'm on the window
Copied into Firefox dev-tools!
Eric
Ted
I'm on the window