The document describes the polymerase chain reaction (PCR) process for amplifying a specific segment of DNA. PCR makes millions of copies of the target DNA segment in a few hours by using DNA polymerase enzyme and primers. It involves repeated cycles of heating and cooling of the DNA sample to denature and renature the DNA. The target DNA segment is amplified selectively between the forward and reverse primers. Key requirements for successful PCR include appropriate primer design and optimization of reaction conditions.