2
2 is a prime number and is the only even prime number.
= 1 x 2 Factorial 2 or 2!
1, 1, 2, 3, 5, 8, 13... A Fibonacci number.
A deuce, a couple, a brace, a duo or a pair...
There are two blades on a pair of scissors and two sides to a piece of paper. People have two hands and so do some clocks. There are two sexes and two sides to an argument. Two-dimensional means that something has just length and width, but no depth.
Two’s company, three’s a crowd all depends on who you happen to be with.
Bi- means two. For example, a bicycle has two wheels and a bigamist has two husbands or two wives.
In binary code numbers are written to the base two. It uses just two symbols, 0 and 1. The numbers 1, 2, 3, 4, 5, 6... become 1, 10, 11, 100, 101, 110...
The letters H, I and X all have two lines of symmetry.
Two has a very special property because2 + 2 = 4and also2 x 2 = 4.