Litmus solution is a natural pH indicator obtained from lichens, specifically the species Roccella tinctoria and Lecanora. These lichens contain dyes known as azo compounds, such as azolitmin, which exhibit different colors in acidic and basic environments. Litmus solution is prepared by extracting these dyes from lichens and dissolving them in water or alcohol. In acidic conditions, litmus solution appears red, while in basic conditions, it turns blue. Litmus is widely used in laboratories to test the acidity or basicity of solutions and is an essential tool in qualitative chemical analysis.