As markets are plunging globally, analysts who study charts are eyeing the key levels to monitor.
The theory behind technical analysis is when prices reach previous levels where participants bought and sold in volume, those levels can be areas of support.
"The market has memory. Historic levels of supply tend to be recognized by market participants in the future when these prices are tested once again," said J.C. Parets, president of Eagle Bay Capital.
As the market falls, CNBC Pro asked expert technicians where the key support levels are: