Painting has taken many forms throughout history and across cultures. Some key points are that painting has been used for both spiritual motifs as well as more secular genres like portraits, landscapes, and still lifes. A variety of techniques have been used including fresco, tempera, oil painting, and others. Cave paintings dating back tens of thousands of years show some of the earliest examples of painting. The Renaissance saw developments in techniques like linear perspective and increased realism. Modernism in painting emerged in the late 19th century and emphasized new approaches that broke from traditions of realism.