What is the difference between svg's x and dx attribute?

Question

What is the difference between svg\'s x and dx attribute (or y and dy)? When would be a proper time to use the axis shift attribute (dx) versus the location attribute (x)?

Answer 1

To add to Scott's answer, dy used with em (font size units) is very useful for vertically aligning text relative to the absolute y coordinate. This is covered in the MDN dy text element example.

Using dy=0.35em can help vertically centre text regardless of font size. It also helps if you want to rotate the centre of your text around a point described by your absolute coordinates.