Once a cherished part of a rapper’s arsenal, the rhyme book has been gradually sliding toward irrelevance. In part, the diminishing importance of the notepad is due to technology—a fate mirrored by that of vinyl, books and other “hard-copy” artistic mediums—but also because of changing attitudes, rhyme techniques and production values within hip-hop itself. As more and more rappers compose rhymes in their heads or on smart phones and computers, we—rap fans, journalists, documentarians—are steadily losing our ability to investigate the process that goes into lyric writing. Just as there’s inherent value in viewing Picasso’s sketches or Kerouac’s original manuscript for his 1957 novel, On the Road, typed on a 120-foot scroll of paper, it’s fascinating to look at Eminem’s handwritten rhymes—made so famous in his semiautobiographical 2002 movie, 8 Mile, and the March 2004 XXL photo shoot that displayed them—and see how Eminem intertwines couplets into dense, witty verses. But beyond such scholarly pursuits, it must be asked: Is rap’s abandonment of the rhyme book affecting the music?

Hip-hop may have evolved as the displaced descendant of African oral tradition, but the written word got involved early. In 1979, when Sugarhill Gang released the nascent genre’s breakout hit, “Rapper’s Delight,” the track included verses Big Bank Hank plucked from Grandmaster Caz’s collection of written rhymes. “When Hank said he needed something to say, I whipped out a book,” says Caz, who never received royalties for writing the lyrics. “The rest is history.” The single became one of the most famous rap songs ever made, and the importance of the notebook was stitched right into its lore.

For many rappers who came of age during the 1980s, having a well-stocked rhyme book was an indication of an artist who took his or her craft seriously. Just as graffiti writers used their “piece books” to plan out designs before they sprayed them on subway cars, rappers used their notebooks to catch the inspiration when it came and to perfect their creations for performance. Like Nas said on his 1994 track “The World Is Yours,” “I sip the Dom P/Watchin’ Ghandi ’til I’m charged/Then writin’ in my book of rhymes/All the words pass the margin.” Some became so attached to their books that they’d carry them with them wherever they’d go. “When I was young, I used to run with a notepad,” Sadat X rapped on Brand Nubian’s 1992 single “Punks Jump Up to Get Beat Down.”

Early in his career, Rakim, the artist credited with modernizing rap via the complexity of his lyrics, misplaced a full rhyme book and spent months worrying that it had fallen into the wrong hands. As a safety precaution, he began writing rhymes in wild-style graffiti lettering—a fact he later alluded to on the 1990 single “Let the Rhythm Hit ’Em.”

“I figured if I lost it, no one would be able to [decode] it,” he says. Rakim believes the use of a notebook is intrinsically tied to thoughtfulness and a deeper commitment to the writing process. “It stands for consciousness in hip-hop,” he says. “If you sit down, it means you’re going to put in time. It’s really important for the culture, and it definitely shows substance.”

Some younger rappers experience a visceral response to the rhyme book in much the same way the tangible quality of vinyl holds appeal to a generation of DJs whose parents didn’t have a turntable in the living room. “When I see a pen and a pad, a feeling gets over me that I can’t explain,” says Lil B, a rapper known for prodigious output and omnipresent hashtag slang on Twitter. “It’s the most epic for me when I’m going stupid nuts.” He doesn’t write lyrics down for his free-associative-based “freestyle” work, but he says he needs paper to properly “get [his] emotions across” for his more meaningful songs.

B claims to have saved every rhyme he’s ever penned. “Seeing the paper wrinkled up and seeing the history, it’s humbling and almost brings tears to my eyes.”

From a historical perspective, the preservation of rhyme books allows outsiders to examine how classic verses were constructed and to gather insight into the artist’s creative process. The Rose That Grew From Concrete, released in 2000, is a collection of Tupac’s poetry from before his rap career blossomed. But as it reproduced the actual pages of his notebooks, in his handwriting, the reader is granted access to early literary quirks—he notates “into” as “in2” and occasionally draws an eyeball, instead of writing “I”—as well as the emerging sociological awareness that threaded through much of his adult work. Similarly, Eminem’s notes show the handiwork of a compulsive writer; his lyrics are often written on napkins and crammed into the corners of pages at off-kilter angles. “He’ll kill you if you look in his book,” says Denaun Porter, a producer and vocalist who has worked with Eminem since his formative years in Detroit. “I don’t know nobody that writes more than him. I’ve been around everybody who’s everybody in the studio, and I’ve never seen a process like that.” Porter says that Eminem is the reason he “stacks lines”—or amasses a reserve of couplets and one-liners that can later be fused into verses.

For all of the pride rappers take in filling notebooks with baroque lyrics, there has always been a special appreciation for rappers who were cool enough to spit bars without breaking a sweat. In the mid-1990s, a few notable rappers began constructing dense, vivid rhymes within the soft circuitry of their brains, instead of on paper (as opposed to freestyling, the verses were premeditated). It started with Jay-Z, as so many trends have. While recording tracks with Brooklyn producer DJ Clark Kent in the early stages of his career, Jay-Z would listen to beats, order lunch, and then lay down vocals without any writing. “It was insane to see, because it was so fast,” says Kent. Jay-Z explained that he tailored rhyme patterns around drum rolls and then used the flow and rhythm to remember the lyrics.

According to Kent, The Notorious B.I.G., who would also become known for composing rhymes in his head, learned the technique from Jay-Z during the making of “Brooklyn’s Finest,” their duet on Jay-Z’s 1996 album, Reasonable Doubt. When Kent brought B.I.G. by Manhattan’s D&D Studios to get on the track, Jay-Z jumped into the booth and redid the song with lyrics that left space for B.I.G.’s verses. Jay then looked at his Brooklyn counterpart. “You ready?” he asked, pushing a pad toward B.I.G. “Your turn.” B.I.G., who had been in the practice of writing out his lyrics up to that point, declined the notebook and opted to record his parts at a later time. “The face on Big was like, ‘What? Are you serious?’” says Kent. “It was a really serious revelation moment.”