Nucleic acid thermodynamics
Nucleic acid thermodynamics is the study of how temperature affects the nucleic acid structure of double-stranded DNA (dsDNA). The melting temperature (Tm) is defined as the temperature at which half of the DNA strands are in the random coil or single-stranded (ssDNA) state.
Source: Wikipedia — Nucleic acid thermodynamics (CC BY-SA 4.0)