Understanding LED datasheet terms
(Continuous) Forward Current - how much maximum current can be put through the LED (30 mA for the LED in question) continuously (as opposed to peak forward current)
(Zener) Reverse current - it has zener diodes internally protecting the LED and these are limited to a certain amount of current before they might fail. The reverse current is that limit.
Peak Forward Current(Duty /10 @ 1KHZ) - tells you that you can exceed the continuous current (30 mA) by using 100 mA ONLY if the duty cycle of the applied current waveform is 10% i.e. you can apply 100 mA for 100 microseconds every 1 milli-second.
Reverse Voltage - this is the nominal reverse voltage of the in-built zener diodes (5 volts) before it starts to heavily conduct (\$I_R\$ >> 50 uA) - see also Zener Reverse Voltage = 5.2 volts at Iz = 5 mA. See also Zener Reverse Current of 100 mA (maximum rating)
Forward Voltage - this is the typical voltage across the LED when feeding it at 20 mA (between 3.0 and 3.6 volts)
Electrostatic Discharge - this tells you that the device is capable of withstanding an ESD event of 4000 volts based on the typical mode of a human (body model) touching the device when in circuit.