Forward direction of dc motor is depend on dc motor spec, CW or CCW.
If you give forward power supply at cw dc motor, so the motor will rotate Clock Wise direction for forward rotate and opposite if you give reverse power supply voltage.
If you give forward power supply at ccw dc motor, so the motor will rotate Counter Clock Wise direction for forward rotate.
Forward powering in dc motor mean that the dc motor is supplied dc voltage to make the dc motor rotate to the right direction as dc motor spec's for forward rotate.
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