Editing 2 (section)

== Mathematics ==
The number 2 is the second natural number after [[1]]. Each natural number, including 2, is constructed by succession, that is, by adding 1 to the previous natural number.<ref>{{cite book| last1=Colman| first1=Samuel| editor-last=Coan| editor-first=C. Arthur| title=''Nature's Harmonic Unity: A Treatise on Its Relation to Proportional Form''| publisher=G.P. Putnam's Sons| location=New York and London| year=1912| url=https://archive.org/details/naturesharmonic00coangoog/page/n26/mode/2up|page=10}}</ref> 2 is the smallest and the only even [[prime number]], and the first [[Ramanujan prime]].<ref>{{Cite web |title=Sloane's A104272 : Ramanujan primes |url=https://oeis.org/A104272 |url-status=dead |archive-url=https://web.archive.org/web/20110428165633/https://oeis.org/A104272 |archive-date=2011-04-28 |access-date=2016-06-01 |website=The On-Line Encyclopedia of Integer Sequences |publisher=OEIS Foundation}}</ref> It is also the first [[superior highly composite number]],<ref>{{Cite web |title=A002201 - OEIS |url=https://oeis.org/A002201 |access-date=2024-11-28 |website=oeis.org}}</ref> and the first [[colossally abundant number]].<ref>{{Cite web |title=A004490 - OEIS |url=https://oeis.org/A004490 |access-date=2024-11-28 |website=oeis.org}}</ref>

An [[integer]] is determined to be [[Parity (mathematics)|even]] if it is [[Division (mathematics)|divisible]] by two. When written in base 10, all [[Multiple (mathematics)|multiples]] of 2 will end in [[0]], 2, 4, 6, or [[8]];<ref>{{Cite OEIS|A005843|The nonnegative even numbers|access-date=2022-12-15}}</ref> more generally, in any even base, even numbers will end with an even digit.

A [[digon]] is a polygon with two sides (or [[Edge (geometry)|edges]]) and two [[Vertex (geometry)|vertices]].<ref name="Wilson2014">{{cite book |last=Wilson |first=Robin |title=Four Colors Suffice |publisher=Princeton University Press |year=2014 |isbn=978-0-691-15822-8 |edition=Revised color}}</ref>{{rp|52}} Two distinct [[point (geometry)|points]] in a [[Plane (geometry)|plane]] are always [[Necessity and sufficiency|sufficient]] to define a unique [[line (geometry)|line]] in a nontrivial [[Euclidean space]].<ref>{{Cite book |last=Carrell |first=Jim |url=https://personal.math.ubc.ca/~carrell/307_chap1.pdf |title=MATH 307 Applied Linear Algebra |chapter=Chapter 1 {{!}} Euclidean Spaces and Their Geometry}}</ref>

A [[Set theory|set]] that is a [[field (mathematics)|field]] has a minimum of two [[Element (mathematics)|elements]].<ref>{{cite web| url=https://proofwiki.org/wiki/Field_Contains_at_least_2_Elements|title=Field Contains at least 2 Elements}}</ref>

[[Binary number|Binary]] is a number system with a [[radix|base]] of two, it is used extensively in [[Computer|computing]].<ref>{{Cite web |title=How computers see the world - Binary - KS3 Computer Science Revision |url=https://www.bbc.co.uk/bitesize/guides/z26rcdm/revision/1 |access-date=2024-06-05 |website=BBC Bitesize |language=en-GB}}</ref>