A codon is a sequence of three nucleotides in DNA or RNA that corresponds to a specific amino acid or signals the termination of protein synthesis. Codons are essential for translating genetic information into proteins, which are crucial for the structure and function of living organisms. In the genetic code, there are 64 possible codons, with 61 coding for amino acids and 3 serving as stop signals. Each amino acid can be represented by more than one codon, a feature known as redundancy. This redundancy helps protect against mutations that could disrupt protein production.