Greek Capital Letter Sigma

Symbol	Format	Data
Σ	Code Point	U+03A3
	TeX	\Sigma
	SVG	Download ↓

The capital Greek letter (capital sigma) is used in algebra to represent the summation operator. Typically, the symbol appears in an expression like this:

In plain language this expression means sum together the expressions represented by starting from and ending when .

Greek Small Letter Sigma | Symbol

The Greek letter σ (sigma) is used in statistics to represent the standard deviation of a population.

Summation | Operator

The summation operator is represented by the symbol Σ (capital sigma) and represents the operation of summing a sequence of expressions together. The operator is used in math to represent the sequence and series.