Positioning elements

What about position? Where do these primitives draw inside the SVG element? What if you wanted to put a circle on the top left and another one on the bottom right? Where do you start?

SVG is positioned by a grid system, similar to the Cartesian coordinate system. However, in SVG (0,0) is the top-left corner. The x axis proceeds horizontally from left to right starting at 0. The y axis also starts at 0 and extends downward. See the following illustration:

What about drawing shapes on top of each other? How do you control the z index? In SVG, there is no z coordinate. Depth is determined by the order in which the shape is drawn. If you were to draw a circle with coordinates (10,10) and then another one with coordinates (10,10), you would see the second circle drawn on top of the first.

The following sections will cover the basic SVG primitives for drawing shapes and some of their most common attributes.