Protein coding refers to the process by which specific segments of DNA are translated into proteins. These segments, known as genes, contain the instructions for building proteins, which are essential for various functions in living organisms. Each gene corresponds to a particular protein, and the sequence of nucleotides in the DNA determines the sequence of amino acids in the protein. During protein synthesis, the information in a gene is first transcribed into messenger RNA (mRNA). This mRNA then travels to the ribosome, where it is translated into a protein. The resulting proteins play crucial roles in processes such as metabolism, immune response, and cell signaling.