The radical symbol by itself is used to denote taking the square root of a number.

Taking the square root of a number is the same as raising the number to the one-half power.

Radical

A radical is used to represent fractional exponents. By itself it is used to represent the square root of an expression, but it also is used to represent higher roots as well.

Exponent

In mathematics superscript text is used to indicate the exponent of some number.