Pi (uppercase Π, lowercase π) is the fifth letter of the Greek Alphabet. It represents "p". In the Greek Numerals system, it has a value of 80.
Its Unicodes are:
U+03C0 π greek small letter pi (HTML: π π)
U+03A0 Π greek capital letter pi (HTML: Π Π)
Other Greek letters used in mathematics include:
- Σ/Sigma : Either used as a Modulo Two-Sum or a N-ary Summation
- ε/Epislon : A Euler (Pronounced "Oiler") constant
- φ/Phi : Commonly used to stand for the golden ratio
And many others.