Difference between Display and Shell

Question

A typical SWT sample code looks like the following code:

final Display display = Display.getDefault();
final Shell shell = createMyShell(display);
shell.open();
while (!shell.isDisposed()) {
    if (!display.readAndDispatch()) {
        display.sleep();
    }
}

What is the difference between Display and Shell?
If multiple windows have to be shown, does each one need an own loop?

Answer 1

You can have multiple shells with a single Display and a single while loop handing event dispatch. Create the display, create the Shell(s) from the Display, and then start the single UI event dispatcher loop. See http://www.chrisnewland.com/av/111/swt-best-practice-single-display-multiple-shells