What is square root spiral?

Select any point in the plane as the origin. From the origin, draw a line of unit length. At its end draw a perpendicular line, also of unit length. This is the first line of the spiral.

Join the end of this second line to the origin - this will be a line of length sqrt(2). At the end of this line draw a perpendicular line of unit length. This is the second line of the spiral.

Join the end of this new line to the origin - this will be a line of length sqrt(3). At the end of this line draw a perpendicular line of unit length. This is the next line of the spiral.

Continue until you have had enough!

Or, follow the link.