A 12-period EMA and 26-period EMA are two moving averages used in calculating a more complex indicator called MACD (Moving Average Convergence Divergence). The MACD turns two EMAs into a momentum indicator by subtracting the longer EMA from the shorter one. Before learning more about MACD, you want to get familiar with its components first. You decide to calculate two EMAs using the Google daily stock prices and plot them in one chart.