The Renaissance was between 1400 A.D. to 1600 A.D. It began in the city states of Italy. The Renaissance means "rebirth" in French. This art reflected back to the classical time of Rome and Greece. This reflection back to the Greek and Romans was not limited to the arts, but all fields like literature, science, and architecture began to look back to the ancients for their inspiration.
One of the major influences in the Renaissance was the change in the social structure of Europe at this time. Before the Renaissance, there were primarily three different social levels; the nobility, the churchmen, and the peasants. During the Renaissance Era a merchant class developed. These wealthy merchants would often hire artists to decorated family chapels in the local church or cathedral. Guilds (or groups of craftworks) would often compete with other guilds in the town by sponsoring large art projects. Later the arts were supported by rich patrician families.
In the Renaissance, we see the first oil painting on canvas. It was also a time where the paintings took on three dimensions by the use of shadow and light. The subject matter included mythical subjects and nature scenes. Artists tried to show differences in proportions (meaning size and location of one thing compared to another in the painting) of their subject matter.
Leonardo DaVinici painted the Mona Lisa during this time. The painting is characteristic of Da Vinici in it's pyramid like setup with a smoky background. Michelangelo took over four years to paint over 6000 square feet of the Sistine Chapel with scenes from the Old Testament Bible. Many other works were also developed during this time. Check out the Middle Age's Art Page and the Middle Age's Biography Page for more on this subject or a particular artist.