a right angle, or a 90 degrees angle
-- an angle that measures 90 degrees -- an angle whose sides are mutually perpendicular
an acute angle
180 degree angle.
flatangle (apex) A straight angle.
That's a "central angle", but the part that really fascinates me is this: What would it look like if you hadan angle whose vertex was in the center of the circle and whose sides didn't intersect ? ? ?
A 180 Degree angle therefore a straight line.
An inscribed angle is an angle whose vertex is on the circle and whose sides are chords.
central angle
The measure of an angle whose sides overlap is 0 degrees. It is than not an angle, but rather a line.
Inscribed angle
An inscribed angle.
A single ray.