Rock and roll (often written as rock & roll or rock 'n' roll) is a genre of popular music that originated and evolved in the United States during the late 1940s and early 1950s, primarily from a combination of African American blues, country, jazz, and gospel music. Though elements of rock and roll can be heard in country records of the 1930s, and in blues records from the 1920s, rock and roll did not acquire its name until the 1950s.

The term "rock and roll" now has at least two different meanings, both in common usage. The American Heritage Dictionary and the Merriam-Webster Dictionary both define rock and roll as synonymous with rock music. Encyclopædia Britannica, on the other hand, regards it as the music that originated in the mid-1950s and later developed "into the more encompassing international style known as rock music". For the purpose of differentiation, this article uses the second definition.

In the earliest rock and roll styles of the late 1940s and early 1950s, either the piano or saxophone was often the lead instrument, but these were generally replaced or supplemented by guitar in the middle to late 1950s. The beat is essentially a blues rhythm with an accentuated backbeat, the latter almost always provided by a snare drum. Classic rock and roll is usually played with one or two electric guitars (one lead, one rhythm), a string bass or (after the mid-1950s) an electric bass guitar, and a drum kit.

Avril Ramona Lavigne (pronunciation: /ˈævrɨl ləˈviːn/; AV-ril lə-VEEN; born 27 September 1984) is a Canadian singer-songwriter. She was born in Belleville, Ontario, but spent most of her youth in the small town of Napanee. By the age of 15, she had appeared on stage with Shania Twain; by 16, she had signed a two-album recording contract with Arista Records worth more than $2 million. In 2002, when she was 17 years old, Lavigne broke onto the music scene with her debut album Let Go.

Let Go made Lavigne the youngest female soloist to reach No. 1 in the UK, and the album was certified four-times platinum by the Recording Industry Association of America. By 2009, over 16 million copies had been sold worldwide. Her breakthrough single, "Complicated", peaked at No. 1 in many countries around the world, as did the album Let Go. Her second album, Under My Skin, was released in 2004 and was her first album to peak at No. 1 on the U.S. Billboard 200, eventually selling more than 10 million copies worldwide. The Best Damn Thing, Lavigne’s third album, was released in 2007, becoming her third No. 1 album in the UK Albums Chart and featuring her first U.S. Billboard Hot 100 No. 1 single, "Girlfriend". Lavigne has scored six number-one singles worldwide, including "Complicated", "Sk8er Boi", "I'm with You", "My Happy Ending", "Nobody's Home", and "Girlfriend". With more than 30 million copies of her albums sold worldwide, Lavigne is one of the top-selling artists releasing albums in the U.S., with over 10.25 million copies certified by the RIAA. Her fourth studio album, Goodbye Lullaby, was released in March 2011. Goodbye Lullaby gave Lavigne her fourth top 10 album on the U.S. Billboard 200 and the UK Albums Chart and her third No. 1 album in both Japan and Australia. Three months after the release of Goodbye Lullaby, Lavigne began work on her fifth album, which will be released on Epic Records following her departure from RCA Records.

Robert Clark "Bob" Seger (born May 6, 1945) is an American rock and roll singer-songwriter, guitarist and pianist.

As a locally successful Detroit-area artist, he performed and recorded as Bob Seger and the Last Heard and Bob Seger System throughout the 1960s. By the early 1970s, he had dropped the "System" from his recordings, and he continued to strive for broader success with other various bands. In 1973, he put together The Silver Bullet Band, an evolving group of Detroit-area musicians, with whom he became most successful. In 1976, he achieved a national breakout with the album Night Moves. On his studio albums, he also worked extensively with the Alabama-based Muscle Shoals Rhythm Section, which appeared on several of Seger's best-selling singles and albums.

A roots rocker with a classic raspy, shouting voice, Seger wrote and recorded songs that dealt with blue-collar themes and was an exemplar of heartland rock. Seger has recorded many hits, including "Night Moves", "Turn the Page", "We've Got Tonight", "Against the Wind", and "Like a Rock", and also co-wrote the Eagles' number-one hit "Heartache Tonight". His iconic recording of "Old Time Rock and Roll" was named one of the Songs of the Century in 2001.