Rosin, derived from tree resin, enhances bow friction on strings, producing clear articulation and sound projection. Its formulation varies between light and dark rosins, with some designed for specific climates or tonal preferences. Top brands include Pirastro (Goldflex and Evah Pirazzi), Hill (Light and Dark), Kolstein (All-Weather), and Andrea (Sanctus). Rosin is essential for violinists, violists, cellists, and bassists, ensuring consistent bow grip and sound production in orchestras, solo performances, and chamber music settings.