DNA-Seq, or DNA sequencing, is a method used to determine the exact order of nucleotides in a DNA molecule. This process allows scientists to read the genetic information encoded in an organism's DNA, which is crucial for understanding genetics, evolution, and disease. The technology behind DNA-Seq has advanced significantly, enabling faster and cheaper sequencing of entire genomes. This has led to breakthroughs in various fields, including personalized medicine, where treatments can be tailored based on an individual's genetic makeup, and in genomics, which studies the structure, function, and evolution of genomes.