Stroke and fill a rectangle, uses the stroke color set in stroke() and the fill color set in fill().
YourScreen.rect(x, y, width, height)
Nothing
YourScreen.beginDraw();
YourScreen.clear();
YourScreen.noStroke();
YourScreen.fill(255, 255, 0);
YourScreen.rect(0, 0, YourScreen.width(), YourScreen.height());
YourScreen.endDraw();