Before Ashoka, the royal communications appear to have been written on perishable materials such as palm leaves, birch barks, cotton cloth, and possibly wooden boards. While Ashoka's administration would have continued to use these materials, Ashoka also had his messages inscribed on rock edicts. Ashoka probably got the idea of putting up these inscriptions from the neighbouring Achaemenid empire. It is likely that Ashoka's messages were also inscribed on more perishable materials, such as wood, and sent to various parts of the empire. None of these records survive now.