What does polymerase chain reaction do

Sometimes called molecular photocopying the polymerase chain reaction is a fast and inexpensive technique used to amplify copy small segments of DNA.

The polymerase chain reaction is a method used to produce millions of copies of particular DNA.

DNA sequences are amplified to generate many copies of a specific DNA segment.

Explanation:

polymerase chain reaction is used to produce a million copies of DNA by amplifying the  DNA sequences exponentially.

PCR method was developed in 1983 by Kary Mullis.

A polymerase chain reaction occurs in three main steps.

thus polymerase chain reaction is used to produce many copies of DNA of specific region of DNA.