Editing Bisection (section)

{{Short description|Division of something into two equal or congruent parts}}
{{distinguish|Dissection}}
{{for-multi|the bisection theorem in measure theory|Ham sandwich theorem|the root-finding method|Bisection method|other uses|Bisect (disambiguation)}}
[[Image:Bisectors.svg|right|thumb|Line DE bisects line AB at D, line EF is a perpendicular bisector of segment AD at C, and line EF is the interior bisector of right angle AED.]]

In [[geometry]], '''bisection''' is the division of something into two equal or [[congruence (geometry)|congruent]] parts (having the same shape and size). Usually it involves a bisecting [[line (mathematics)|line]], also called a ''bisector''. The most often considered types of bisectors are the ''segment bisector'', a line that passes through the [[midpoint]] of a given [[line segment|segment]], and the ''angle bisector'', a line that passes through the [[Apex (geometry)|apex]] of an [[angle]] (that divides it into two equal angles).
In [[three-dimensional space]], bisection is usually done by a bisecting [[plane (geometry)|plane]], also called the ''bisector''.