RNA interference (RNAi) is a natural cellular process that regulates gene expression by silencing specific genes. It involves the introduction of double-stranded RNA molecules that are complementary to a target gene's messenger RNA, causing degradation of the mRNA and thus inhibition of protein production. RNAi has become a powerful tool in research for studying gene function, as well as a potential therapeutic approach for treating various diseases such as cancer and viral infections. The discovery of RNAi has revolutionized the field of molecular biology and has opened up new possibilities for understanding and manipulating gene expression in living organisms.