Cryptography is a cornerstone of the modern security technologies used to protect information and resources on both open and closed networks. It is most often associated with scrambling plaintext into ciphertext a process called encryption, then back again, known as decryption. Cryptography software or hardware devices use mathematical formulas to change text from one form to another. Modern cryptography is heavily based on mathematical theory and computer science practice; cryptographic algorithms are designed around computational hardness assumptions, making such algorithms hard to break in practice by any adversary.