How can I get windowWidth, windowHeight, pageWidth, pageHeight, screenWidth, screenHeight,
You can also get the WINDOW width and height, avoiding browser toolbars and other stuff. It is the real usable area in browser's window.
To do this, use:
window.innerWidth and window.innerHeight properties (see doc at w3schools).
In most cases it will be the best way, in example, to display a perfectly centred floating modal dialog. It allows you to calculate positions on window, no matter which resolution orientation or window size is using the browser.