Caster Sugar, Castor Sugar,Superfine Sugar or Baker's Special comes white or golden brown.
Caster sugar comprises very fine crystals (less than 25mm), so is not a powder like icing sugar. Caster sugar is airy, firm and voluminous.
Caster sugar gives a fine and firm texture to cut out biscuits, and blends beautifully in cake mixes. Caster sugar is what you need for meringues.