A circle is considered to have an infinite number of sides because it is a continuous curve with no corners or edges. In geometric terms, when defining a polygon, the number of sides is finite, but a circle's smooth, unbroken shape leads to the concept of having infinitely many infinitesimal sides. Thus, while a circle does not have sides in the traditional sense, it can be described as having infinite sides in a mathematical context.
a circle is a circle - no sides at all
Archimedes created the formula for measuring the circumference of a circle he used many-sided polygons, both inside and out to approximate it.
a semi-circle
Zero in the normal course of events. You could say you can approximate a circle by an infinite-sided polygon, and then you would have infinite sides and corners. Or you could say a circle has an inside and an outside.
Pentagram
a circle is a circle - no sides at all
a circle
Circle
There is no such thing as a 1 sided shape nor a two sided shape.
A 9-sided "circle" is an nonagon or enneagon.
Archimedes created the formula for measuring the circumference of a circle he used many-sided polygons, both inside and out to approximate it.
a circle
A circle!
Circle.
a circle
a circle
A circle