Problem: Background: Stephen Ray Vaughan (October 3, 1954 - August 27, 1990) was an American musician, singer, songwriter, and record producer. In spite of a short-lived mainstream career spanning seven years, he was one of the most influential guitarists in the revival of blues in the 1980s. AllMusic describes him as "a rocking powerhouse of a guitarist who gave blues a burst of momentum in the '80s, with influence still felt long after his tragic death." Born and raised in Dallas, Texas, Vaughan began playing guitar at the age of seven, inspired by his older brother Jimmie.
Context: In May 1969, after leaving the Brooklyn Underground, Vaughan joined a band called the Southern Distributor. He had learned The Yardbirds' "Jeff's Boogie" and played the song at the audition. Mike Steinbach, the group's drummer, commented: "The kid was fourteen. We auditioned him on 'Jeff's Boogie,' really fast instrumental guitar, and he played it note for note." Although they played pop rock covers, Vaughan conveyed his interest in the addition of blues songs to the group's repertoire; he was told that he wouldn't earn a living playing blues music and the band parted ways. Later that year, bassist Tommy Shannon walked into a Dallas club and heard Vaughan playing guitar. Fascinated by the skillful playing, which he described as "incredible even then", Shannon borrowed a bass guitar and the two jammed. Within a few years, they began performing together in a band called Krackerjack.  In February 1970, Vaughan joined a band called Liberation, which was a nine-piece group with a horn section. Having spent the past month briefly playing bass with Jimmie in Texas Storm, he had originally auditioned as bassist. Impressed by Vaughan's guitar playing, Scott Phares, the group's original guitarist, modestly became the bassist. In mid-1970, they performed at the Adolphus Hotel in downtown Dallas, where ZZ Top asked them to perform. During Liberation's break, Vaughan jammed with ZZ Top on the Nightcaps song "Thunderbird". Phares later described the performance: "They tore the house down. It was awesome. It was one of those magical evenings. Stevie fit in like a glove on a hand."  Attending Justin F. Kimball High School during the early 1970s, Vaughan's late-night gigs contributed to his neglect in his studies, including music theory; he would often sleep during class. His musical career pursuit was disapproved by many of the school's administrators, but he was also encouraged by many people to strive for a career in art, including his art teacher. In his sophomore year, he attended an evening class for experimental art at Southern Methodist University, but bailed when it conflicted with rehearsal. Vaughan later spoke of his dislike of the school and stated that he had to receive a daily note from the principal about his grooming.
Question: What did Vaughan have to say about that?
Answer: he was also encouraged by many people to strive for a career in art, including his art teacher.

Problem: Background: Avenged Sevenfold (sometimes abbreviated as A7X) is an American heavy metal band from Huntington Beach, California, formed in 1999. The band's current lineup consists of lead vocalist M. Shadows, rhythm guitarist and backing vocalist Zacky Vengeance, lead guitarist and backing vocalist Synyster Gates, bassist and backing vocalist Johnny Christ, and drummer Brooks Wackerman. Avenged Sevenfold is known for its diverse rock sound and dramatic imagery in album covers and merchandise. Avenged Sevenfold emerged with a metalcore sound on the band's debut Sounding the Seventh Trumpet and continued this sound through their second album Waking the Fallen.
Context: The band's influences include Guns N' Roses, Iron Maiden, Megadeth, Pantera, Bad Religion, Dream Theater, Motorhead, Metallica, Black Sabbath, Led Zeppelin, The Rolling Stones, In Flames, At the Gates, Helloween, Queensryche, System of a Down, AC/DC, NOFX, Alice in Chains, Black Flag, Corrosion of Conformity, Suicidal Tendencies, Misfits, Slayer, The Vandals, Soundgarden, Rage Against the Machine, Korn, Slipknot, Deftones, Beastie Boys, Biohazard, Type O Negative, Anthrax and AFI.  The band has been categorized under many genres of heavy music. Mainly categorized as heavy metal, hard rock, progressive metal and metalcore, Avenged Sevenfold's music has evolved over most of the band's career. At first, the band's debut album Sounding the Seventh Trumpet consisted almost entirely of a metalcore sound; however, there were several deviations from this genre, most notably in "Streets", which shows a punk rock style, and "Warmness on the Soul", which is a piano ballad. On Waking the Fallen, the band displayed a metalcore style once more, but added more clean singing and leaned a bit more towards metal and bit less close to hardcore. In the band's DVD All Excess, producer Andrew Murdock explained this transition: "When I met the band after Sounding the Seventh Trumpet had come out before they had recorded Waking the Fallen, M. Shadows said to me 'This record is screaming. The record we want to make is going to be half-screaming half-singing. I don't want to scream anymore. And the record after that is going to be all singing'."  On City of Evil, Avenged Sevenfold's third album, the band chose to abandon the metalcore genre, using a more hard rock and heavy metal style. Avenged Sevenfold's self-titled album, however, has some experiments with other music genres than that from City of Evil, most notably in "Dear God", which shows a country style and "A Little Piece of Heaven", which is circled within the influence of Broadway show tunes, using primarily brass instruments and stringed orchestra to take over most of the role of the lead and rhythm guitar. Nightmare contains further deviations, including a piano ballad called "Fiction", progressive metal-oriented track "Save Me" and a heavy metal sound with extreme vocals and heavier instrumentation on "God Hates Us". The band's sixth studio album Hail to the King shows more of a classic metal sound and a riff-oriented approach. On their newest album The Stage, the band explores further into progressive metal, blending it with elements of thrash metal. In the past, Avenged Sevenfold has also been described as alternative metal, screamo, and pop punk metal.  The band has been criticized for "not being metal enough". Vocalist M. Shadows responded to this with, "we play music for the sake of music, not so that we can be labeled a metal band. That's like telling us we aren't punk enough. Who cares?" Avenged Sevenfold is one of the notable acts of the New Wave of American Heavy Metal.
Question: Which ones were the most popular?
Answer:
"Fiction", progressive metal-oriented track "Save Me" and a heavy metal sound with extreme vocals and heavier instrumentation on "God Hates Us".