That unmistakable, hard-driving guitar line is what makes "Sweet Home Alabama" the great song it is, the epitome of Skynyrd's famous heavy-rocking sound.
Ed King, one of the band's three (!) lead guitarists, said that the chords and solos for "Sweet Home Alabama" came to him in a dream, crystal clear, chord for chord and note for note. Only Ed King knows for sure whether that's really history or myth, but either way, we know that the next morning he played the whole song for his bandmates and a legend was born.
On top of that signature riff, they built a dense wall of sound. Multiple guitar solos, often running over each other in the mix. A euphoric piano solo vaguely reminiscent of Jerry Lee Lewis's wild "Great Balls of Fire." Ronnie Van Zant's expressive vocals. Even harmonizing female backup singers (a first for the band). The end result was one of the most irresistibly catchy hard rock songs of all time.
So… "Turn it up!"