Right angle Right angle In geometry and trigonometry, a right angle is an angle of exactly 90° (degrees), corresponding to a quarter turn. If a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. The term is a calque of Latin "angulus rectus"; here "rectus" means "upright", referring to the vertical perpendicular to a horizontal base line. Closely related and important geometrical concepts are perpendicular lines, meaning lines that form right angles at their point of intersection, and orthogonality, which is the property of forming right angles, usually applied
How Many More Years of the power chord. T-Bone Burnett said of the recording: The first major breakthrough Sam [Phillips] made was with Howlin' Wolf. That's when he started bringing the bass and drums up loud. Back in those days the bass and drums were background instruments; it was all about the horns and the piano, the melody instruments, and Sam brought the rhythm section right up front, and that became rock 'n' roll. That was a big shift... In some ways "How Many More Years" by Wolf would be the first rock ’n’ roll song because that has the guitar lick that became