THe Slash refers to slide.
2/4 = put your finger on 2nd fret, pluck the string. While teh string is vibrating, slide your finger (pressed down on the string) and bring it to stop at 4th fret.
Note: the string must be vibtrating even when you bring your finger to 4th fret.
Only then it will be executed correctly.
0/2/0 should mean you pluck the string with no fretting, bring in your finger press on first fret and slide it to 2nd. and then again slide the fingewr back to the nut (0th fret).
All this should be done very fast and fluently.
You donít get what you deserve, you get what you negotiate.