• Or, when you know the Circumference:
  • The circle is a  shape (two dimensional):
  • A line that goes from one point to another on the circle's circumference is called a Chord.
  • A line that "just touches" the circle as it passes by is called a Tangent.

The Circle


The Circle Maker is a book you should pick up and read. I know of several others who are reading it and are being challenged. Grab a copy and be challenged to be a circle maker.

After reading The Circle Maker one can’t help but put the book down and feel the need to become more disciplined and persistent in prayer. Batterson does a good job of laying out practical steps and encouragement to follow through on that desire. The reality that kept coming back to me was that prayer is work and requires discipline to continue to circle the dreams and fears each one of us have.


The radius of the circle is shown in the above figure.

Kalden is, in fact, the elusive 'Wise Man' Ty Gospodinov, the original inventor and founder who came up with the idea for the company. Mae agrees to meet him in secret and he tells her that a totalitarian regime will soon arise if nothing is done to stop it, equating it to a surveillance society. He explains the need for privacy in the digital age and asks her to help him take down the Circle, saying he cannot do it alone. Mae thinks that he is crazy, but pretends to go along with him, but then betrays him by telling the other founders of the Circle what has happened, who ensure that Ty is silenced. The book ends with Mae looking at Annie in the hospital, wondering when the time will come that people's thoughts will be knowable as public information, saying that "the world deserves nothing less and will not wait".