Kill’em All  by Metallica

When the unknown Metallica released Kill 'Em All back in 1983, neither the audience nor the critics could categorize the album anywhere. To some, it seemed to be something close to punk, others understood it as heavy metal, but perhaps not.

The compositions were a group effort by all the members of the band. Everyone had something to offer. Among the members of the band was Dave Mustaine, before he was expelled by the others, who has stated that it was the best album he recorded in his entire career. The production was credited to Paul Curcio.

Eventually, Kill 'Em All defined and set the standards for the entire thrash metal scene. It is one of those albums that, upon its release and with what it offers, brings about changes in music. It probably did well for an album initially estimated to sell 15,000 copies, as that was the number of initial copies prepared by their record company. The album has sold 4,500,000 copies in the U.S. alone. Indicative of what happened is that the album entered the Billboard Top-200 three years after its release (!)