During translation, a ribosome reads a sequence of mRNA (messenger RNA) in groups of 3 bases called codons. The ribosome then calls for a tRNA (transfer RNA) molecule with another group of 3 bases that correspond to the codon. This group of bases is called an anticodon. The ribosome strings the anticodons together to create an amino acid chain, and then final processing occurs to create the desired protein. In a way, the ribosome is translating the language the mRNA is using into a language that the tRNA can understand, hence why translation is used.