Danae dan-Ah-ee said:
Whether it's flat-leaved parsley or coriander, the only thing, probably, that it's now worth keeping for would be the seed. If you like its flavour, keep it and then google how to propagate it from seed. Coriander is very easy; parsley requires patience!
What does it smell like? Crush a keaf if you're not certain it's an edible plant.