the.com/function
a machine that swallows input, digests it, and returns something it never had to keep.
means A function is a defined operation or role that takes something in and produces a corresponding result, whether in math, computing, or everyday duties.
from From Latin functio, 'a performance, an executing,' from the verb fungi, 'to perform, discharge, or carry out a task.' It entered English in the 1500s meaning the proper activity or duty of something, and by the 1700s mathematicians had borrowed it for the precise sense of one quantity depending on another. The social 'function' — a gathering with a purpose — is the same word wearing a nicer coat.
- origin
- Leibniz coined the term in 1673
- math root
- each input maps to exactly one output
- pure ideal
- same input, same output, no side effects
- first-class
- can be passed around like any value
- biology too
- organs are defined by what they do