When did Jay Z become Jay Z? For some, the answer is as simple as when he took his name. For others, he emerged fully-formed on his tough-talking debut, Reasonable Doubt, or on his glossier Bad Boy-assisted follow-up, In My Lifetime, Vol. 1. But for many, the Jay Z we think of today—the smooth hit-maker, the cocky empire-builder, the clever businessman—didn't really exist until Vol. 2... Hard Knock Life, his chart-busting 1998 record that celebrated its 15th anniversary this past Sunday. It was a formative album.

Building on the commercial success of Vol. 1, the more stream-lined Vol. 2 saw Jay Z going for the jugular. Aided by the mainstream gate-crashing hit "Hard Knock Life (Ghetto Anthem)," the album sold millions of copies while still managing to retain the cold-eyed detachment and precision of his early work. Far from being a full-fledged pop makeover, the album combined some of the hottest and most daring producers of the era (Swizz Beatz, Timbaland) with some of Jay's most intricate rhymes. As Wale points out in his review, it might be considered a backpack record if it was released today, packed with verses from hard-headed rappers like DMX, The LOX, Beanie Sigel and more. It's hardly kid stuff.

Despite the runaway success of the "Hard Knock Life (Ghetto Anthem)" single, Vol. 2 has a strange reputation critically. While not as acclaimed as the more varied Vol. 3 or as beloved as the more reflective Blueprint, it's reputation is primarily defined by its sales. That's perhaps fitting for an album that often feels cold and calculating, but it's not necessarily fair: There's a lot going on underneath the shiny car surface of Vol. 2. To celebrate the record's 15 year anniversary and its enduring legacy, XXL has delved back into the album and its history, finding 15 things you might not know about Jay Z's Vol. 2... Hard Knock Life.