Simple Moving Average (SMA)

Interpretation / Algorithm
All Moving Averages with Metastock screenshot [paritech.com]
Description with math formula [FMLabs.com]
Arithmetic Mean [wikipedia.org]
Technical Analysis A to Z by Steven B. Achelis [equis.com]
Technical Analysis Studies [prophet.net]

Product Implementation	Function / Formula / Script / Source Code
Genius Trader [geniustrader.org]	PERL Script - GT::Indicators::SMA [geniustrader.org]
TA-Lib [ta-lib.org]	C/C++ Source Code - TA_SMA()
Wealth-Lab [wealth-lab.com]	ChartScripts using SMA [wealth-lab.com]

Related Links
Technical Analysis Studies - Envelope [prophet.net]