By
default, the x and y axes are parallel to the horizontal
and vertical sides of the document window.
Choose Edit > Preferences >
General (Windows) or Illustrator > Preferences > General (Mac OS).
Specify an angle in the Constrain Angle text box. A positive
angle rotates the axes counterclockwise; a negative angle rotates
the axes clockwise.
Rotating the axes is useful if your artwork consists of
elements that are rotated to the same angle, such as a logo and
text displayed on a 20° angle. Instead of rotating each element
you add to the logo, you can simply rotate the axes by 20°. Everything
you draw is created along the new axes.
Object aligned with default axes (left) compared to alignment
with axes rotated 20° (right)
The following
objects and actions are not affected by the new axes: