What are average periods?

The main moving average periods to focus on are 21, 55, 100, and 200. Shorter-term traders may consider looking at the 9- and 14-period moving averages.

I read the above in a book. What does it mean? I would love some clarification on this. What are moving average periods?

Silky Smooth Moving Averages | Moving Averages | Learn Forex Trading

Thanks yunny1 to share link about Smooth Moving Averages. It is helpful for me as well.

Check out the Baby Pips School, they explain how moving averages work in there.

Yep, the BabyPips School is always helpful.

The ‘21, 55, 100, 200’ define how far back the MA is being calculated.
If you’re looking at an H1 chart and plot a ‘[I]100 SMA[/I]’, it’ll use the last [I]one hundred[/I] 1-hour bars for its calculation.
If you’re looking at an M15 chart and plot a ‘[I]55 SMA[/I]’, it’ll use the last [I]fifty-five[/I] 15-minute bars for its calculation.

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