Eventually various groups in opposition to the Roman Empire and its dominiation were to acquire the new technology by various means - though other groups were to reject this aspect of imperial control. Woodblock printing was developed as a cheap alternative to the expensive printing presses and metal required, being based in part upon the concepts used in the use of seals: lower grade paper and other materials could be used. Christianity and other faiths, and separatist groups promoted their message using this new technology which removed the possibility of identification by handwriting.