Besides singing Madonna has the ability to play several musical instruments. She learned to play drum and <answer>guitar</answer> from her then-boyfriend Dan Gilroy in the late 1970s before joining the Breakfast Club line-up as the drummer. This helped her to form the band Emmy, where she performed as the <answer>guitar</answer>ist and lead vocalist. Madonna later played <answer>guitar</answer> on her demo recordings. On the liner notes of Pre-Madonna, Stephen Bray wrote: "I've always thought she passed up a brilliant career as a rhythm <answer>guitar</answer>ist." After her career breakthrough, Madonna focused mainly in singing but was also credited for playing cowbell on Madonna (1983) and synthesizer on Like a Prayer (1989). In 1999, Madonna had studied for three months to play the violin for the role as a violin teacher in the film Music of the Heart, before eventually leaving the project. After two decades, Madonna decided to perform with <answer>guitar</answer> again during the promotion of Music (2000). She took further lessons from <answer>guitar</answer>ist Monte Pittman to improve her <answer>guitar</answer> skill. Since then Madonna has played <answer>guitar</answer> on every tour, as well as her studio albums. At the 2002 Orville H. Gibson Guitar Awards, she received nomination for Les Paul Horizon Award, which honors the most promising up-and-coming <answer>guitar</answer>ist.
What instrument does Madonna play on her demo recordings?
guitar