∞
Symbol  Format  Data 

∞  Code Point 
U+221E 
TeX 
\infty 

SVG 
In math, the infinity symbol () is used to represent the concept of infinity, an idea describing something that is unbounded or limitless. Typically, the symbol is used in an expression like this:
In plain language, this expression represents the limit of the expression as the variable approaches infinity.
The limit operator describes the result of an expression as a variable approaches a value. The operator is used in calculus to formalize what mathematicians mean by approach.
A series is the sum of the terms of a sequence. It can be finite or infinite, depending on the underlying sequence. In calculus, series are used to approximate functions, study convergence and divergence, and understand the behavior of infinite sums.