To HORIZONS and MAN WITH A HAT :
Quoting Journey's biography on PA :
Journey biography
JOURNEY is a American band who started playing in the early months of '73 in San Francisco. The music of JOURNEY is divided in 2 parts, the one from early 1973 'till 1977 when guitarist Neal Schon and keyboardist Gregg Rolie, both of Santana fame, met with bassist Ross Valory and drummer Prairie Prince from The Tubes (replaced later by Aynsley Dunbar) in the summer of 1974. Their music back then was jazz rock with progressive elements and fusion interplays , instrumental passages being pretty much top notch thanks to Neal Schon's driving riffs and solid bass lines of Valory, while the keyboards (still mostly the Hammond organ) of Rollie was something "á la Santana" but less latino-inspired.
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This thing will change next year, in 1978, when it is considered that the band stepped into a new period, the second one. After three albums that were considered dissapointing sales-wise, but were in fact Journey's most progressive ones from the entire discography, Journey hired a better vocalist - Steve Perry. Actually the change was mostly enforced by CBS, or else they would drop the band's recording contract. The results were immediately felt on the fourth album, Infinity, released in 1978, who was sold in over one million copies, more than the previous albums altogether. But the sound changes were almost dramatic. From that jazz-fusion progressive music they turned in an AOR - hard rock band, not far from what FOREIGNER, STYX or BOSTON played during the same period.
Feel free to change their bio if you disagree with the passages highlighted in red.