strokeRekt - контур. 
fullRect - заливка. 
Значения по умолчанию

context.strokeStyle = "red";
context.fillStyle = "blue";
context.lineWidth = 6.5;
		

context.strokeStyle = "red";
		
context.setLineDash([15,5]);
context.strokeRect(5, 40, 100, 100);
		
context.strokeStyle = "blue";
context.setLineDash([2,5,6]);
context.strokeRect(125, 40, 100, 100);
		
context.strokeStyle = "green";
context.setLineDash([2]);
context.strokeRect(245, 40, 100, 100);
		

context.lineJoin = "miter";
context.strokeRect(5, 40, 100, 100);
context.lineJoin = "bevel";
context.strokeRect(122, 40, 100, 100);
context.lineJoin = "round";
context.strokeRect(240, 40, 100, 100);
		

context.globalAlpha = 0.5;