Real-time PCR is a lab technology of molecular biology based on polymerase chain reaction (PCR). It monitors the amplification of a targeted DNA molecule during the PCR, i.e. in real time, and not at the end, as in the traditional PCR. Real-time PCR and RT-PCR (also known as quantitative or qPCR) allows the quantification of exact quantity of DNA, cDNA, and RNA targets to starting quantity. During each cycle the fluorescence is measured, which greatly increases the dynamic range of the reaction, because the amount of fluorescence is proportional to the amount of PCR product. PCR products can be detected using fluorescent dyes, which are linked to sequential-specific detection with double-stranded DNA or fluorescently labels.