The Renaissance was a period between the 14th and 17th centuries that saw a rebirth of interest in classical learning. Major Italian cities like Florence and Venice became centers of trade and patronage for artists. Humanism emphasized the abilities of humans and the importance of education. Artists began using techniques like perspective and realistic proportions. Famous Renaissance artists included Michelangelo, Leonardo da Vinci, and their works like the Pieta, Mona Lisa, and The Last Supper. Literature flourished with Shakespeare's plays. Johannes Gutenberg's printing press made books more widely available. Exploration and scientific discoveries increased European knowledge. The Protestant Reformation began as religious reforms but led to the establishment of new Christian denominations in Europe.