DNA binding refers to the interaction between proteins or other molecules and DNA strands. This process is crucial for various biological functions, including gene expression, DNA replication, and DNA repair. Proteins that bind to DNA can either promote or inhibit these processes, depending on their specific roles. Different types of proteins, such as transcription factors and enzymes, have unique binding sites that recognize specific DNA sequences. This specificity allows them to regulate which genes are turned on or off in a cell, ultimately influencing cellular behavior and function.