Sugar syrup is the base for a lots of cocktails, sorbets and fruit drinks, it's is worth keeping in your fridge as it keeps for weeks and weeks. This syrup is 2:1 ratio, some syrups call for a thicker 1:1 ratio, which is just equal parts water to equal parts sugar.
Put the sugar into a small saucepan, add the water. Bring to the boil until the sugar is fully dissolved. Cool and store in a jug or jar in the fridge.