Arepas are little Venezuelan breads made with pre-cooked corn flour that you can find in specialised grocery stores.
Dissolve the salt in the water and pour in the melted butter and the corn flour.
Knead until you get a homogeneous dough ball. Add a bit of flour if it seems too wet.
Divide the dough ball in 4 flattened balls (about 1 centimetre thick).
In a pan, fry in a bit of butter for about 5 minutes on each side until golden.