In math, the left curly brace is used with the right curly brace symbol to represent a set object. Typically the symbol is used in an expression like this.
In plain language this means the set containing the elements , and .
Right curly brace.
The left square bracket symbol is used in math to delineate the start of a matrix.
The right square bracket symbol is used in math to delineate the end of a matrix.
The left parenthesis symbol is used to mark the start of an expression, or in the case of a function, a list of expressions.
The right parenthesis is used to mark the end of a group.
The notation for a set is two curly braces containing the elements of the set separated by commas.