Classic rock is about heavy hooks, power chords, and tight harmonies, but it’s also about letting loose and enjoying the good times — and there’s no better time than Friday evening, when we pick up our paycheck, punch out of work, and enjoy a couple days of much-needed rest and relaxation.

This Friday, we're paying tribute to one of the Rock and Roll Hall of Fame's Class of 2013 inductees, and a song whose distorted, hard-charging opening riff is one of classic rock radio's biggest clues that it's time to turn up the volume and hit the gas. We're talking, of course, about Heart's 'Barracuda.'

A huge early success for the band, 'Barracuda' peaked just outside the Top 10 of Billboard's Hot 100 during its initial release in 1977, bringing Heart its third Top 40 hit -- and an added measure of vindication following an ugly split with their former label.

As outlined in our Top 100 Classic Rock Songs entry on 'Barracuda' (which placed it at No. 41), the song was inspired by vocalist Ann Wilson's aggravation in the wake of a tasteless ad campaign that falsely suggested she was in an incestuous lesbian love affair with her sister and bandmate Nancy. After suffering through a creepy backstage encounter with a man who'd obviously been emboldened by the ad, Ann holed up in her hotel room and penned the lyrics to 'Barracuda,' later finished off as a collaborative effort with Nancy, guitarist Roger Fisher, and drummer Michael DeRosier.

Of course, rock radio playlists have never exactly been a breeding ground for feminist anthems, but part of 'Barracuda's' genius is the deliberate obliqueness of the lyrics. While the song's arrangement gives off an obviously angry vibe and it's clearly intended as a kiss-off to someone who's done the singer wrong, it isn't exactly Helen Reddy, and those lines about porpoises and western pools helped Heart score a hit with plenty of people who might not have cared one way or the other about the plight of the groundbreaking female rock artists.

Sadly, this wouldn't be the last time Heart would find itself swimming against the tide in terms of prevailing sexual attitudes, as their corseted and hairsprayed reign on the pop charts during the late '80s would eventually attest. But there's no arguing with the band's legacy, or this song's timeless ability to use a few well-chosen chords to let the listener know it's time to blow off some steam. Fortunately for you, we've embedded 'Barracuda' below, so hit "play," turn it up, and let the weekend start now.

Heart, 'Barracuda'

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