Traditional Pop music of the 1950's refers to the music that was popular before rock music came into the mainstream in the middle of the fifties, it also refers to music that was popular at the same time as the beginning of rock music during the rest of the decade but remained largely free of rock influences. Some examples of traditional pop artists who were popular during the decade were Perry Como, Tony Bennett, Nat King Cole, Patti Page and Dean Martin. They sang a lot of original material, but a lot of their most popular hits were American standards, or songs that had been released many years previously but were already well known by the public. Most songs in this genre could be classified as being simple and melodic with catchy lyrics. Many of the traditional pop artists of the 1950's were interpreters of pop standards who would take the old well-known songs and put their own individual style into it. Some of the most popular interpreters were Ella Fitzgerald, Frank Sinatra, Peggy Lee, and Doris Day. This genre was greatly influenced by jazz, swing and big band.