The Simple Moving Average (SMA) is an arithmetic moving average 

The Simple Moving Average (SMA) is calculated by adding the closing price of a  certain number of time periods and then dividing this total by that number of time periods.

Example:

A 5 period Simple Moving Average (SMA) is equal with the sum of the closing price of the last five periods, divided by five.

A 20 period Simple Moving Average (SMA) is equal with the sum of the closing price of the last twenty periods, divided by twenty.

List of Moving Averages Indicators in Technical Analysis:

• Adaptive Moving Average - AMA
  
• Simple Moving Average - SMA
• Exponential Moving Average - EMA
• Triangular Moving Average - TRIMA
• Time Series Moving Average
• Weighted Moving Average (WMA)