Nucleases are enzymes that break down nucleic acids, such as DNA and RNA, into smaller components. They play a crucial role in various biological processes, including DNA replication, repair, and degradation. Nucleases can be classified into two main types: exonucleases, which remove nucleotides from the ends of nucleic acid strands, and endonucleases, which cut nucleic acids at specific internal sites. These enzymes are essential for maintaining the integrity of genetic material and regulating cellular functions. In research and biotechnology, nucleases are used in techniques like gene editing and molecular cloning, making them valuable tools in genetic engineering and therapeutic applications.