Where the jazz Real Book uses complex chord extensions (#11, b13, etc.), The Real Pop Book simplifies changes to match how the actual recordings are played. You get the exact chord voicings, bass lines, and rhythmic hits that make the song recognizable.
To understand the value of this book, one must understand the "Fake Book" concept. A fake book contains the melody line, lyrics, and chord symbols for a song. It allows a musician to "fake" their way through a song they don't know perfectly by reading the skeletal structure. The Real Pop Book Pdf