What does it really mean ?
God, that's such an amateur question to ask...that can easily be searched or looked up in less than a minute.
Watch this four hour documentary ten times,
The Ascent of Money: A Financial History of the World. Niall Ferguson, 2009
if you're able to do that, you're an ET...or prepared, to be an ET.
Young and/or inexperienced traders are like the Karate Kid...while the more wiser and successful one's are Mr. Miyagi