|"Is this all real? Or has this been happening inside my head?"
The subject of this article is a real-life person, company, product, or creative work that has been mentioned "in-universe" in a canon source. The Harry Potter Wiki is written from the perspective that all information presented in canon is true (e.g., Hogwarts really exists), and, as such, details contained in this article may differ from real world facts.
Used as an instrument
A rhythm guitar is the use of a guitar to provide rhythmic chordal accompaniment for a singer or other instruments in a musical ensemble. In ensembles or "bands" playing within the acoustic, country, blues, rock or metal genres (among others), a guitarist playing the rhythm part of a composition supports the melodic lines and solos played on the lead instrument or instruments, be they string, brass, wind, keyboard or even percussion instruments, or simply the human voice. In the most commercially available and consumed genres, electric guitars tend to dominate their acoustic cousins in both the recording studio and the live venue. However the acoustic guitar remains a popular choice in country, western and especially bluegrass music, and is used almost exclusively in folk music. Heathcote Barbary played rhythm guitar with the Weird Sisters.