What is the difference btw current amplification factor and current gain?

current amplification factor can be defined as the ratio of the output current to the ratio of input current . when its passing through an electrical devices . 
so, it gives us the amount of current gain as it flows through . 
AND THERE IS NO BESIC DIFFRENCE BETWEEN THE CURRENT GAIN AND THE CURRENT AMPLIFICATION FACTOR ( BITA ) 
IN current amplification the transister are gaining the current , so, their name are current gain factor . 
HOPE IT CLEARS YOUR DOUBT 
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