invariant section

== English == === Alternative forms === (programming) INVARIANT section === Etymology === (law): Coined by Free Software Foundation in free software copyright licenses. === Noun === invariant section (plural invariant sections) (law) Something that must not be removed or modified during redistribution. (mathematics) A section that will not vary through changing state. (programming) A property that does not change through a program's execution. ==== Usage notes ==== (mathematics): Often used in the form X-invariant section, implying a section that remains constant while X is being changed. === Further reading === Text of the GNU Free Documentation License possibly first legal use.