GarageBand was first released on January 6, 2004. GarageBand has always included an extensive collection of sounds (loops), software instruments, and amplifier effects. In 2004, Apple released its first add-on pack to GarageBand, referred to as the GarageBand Jam Pack, a collection of loops, software instruments, and guitar amps.
In 2006 Apple released several GarageBand Jam Pack collections, including Remix Tools, Rhythm Section, Symphony Orchestra, World Music, and Voices.
This is the retail box for GarageBand Jam Pack: Rhythm Section. According to the box, “This Jam Pack contains over 2000 royalty-free, prerecorded Apple Loops which can be used with GarageBand, Logic Express, Logic Pro, Soundtrack Pro, and any other software that reads AIFF files. The box featured “Basses and guitars galore” and additional Rhythm kits.
Source: Wikipedia