′
Symbol  Format  Data 

′  Code Point 
U+2032 
TeX 
\prime 

SVG 
The prime symbol is used in math to denote the derivative of a function. Typically, the symbol is used in an expression like this:
In plain language, this expression represents the first derivative of the function . Note: this site uses a different notation for the derivative. Read more…
The apostrophe is a punctuation mark used in written language. In mathematics, it is often used to denote a derivative (in calculus) and a complement (in set theory).