Next generation sequencing (NGS) involves chemical assays other than traditional Sanger sequencing to sequence DNA. The basic steps of NGS are: 1) library preparation where DNA is fragmented and adapters are ligated, 2) clonal amplification where fragments are amplified, and 3) sequencing reactions using techniques like pyrosequencing or reversible dye terminators to determine the sequence. The sequenced fragments are then analyzed bioinformatically to map reads and assemble sequences.