Cryptography is a language used to provide security for information, such as passwords for email accounts. Cryptography is not only limited to online websites, but can reach any type of digital platform, such as a log-in screen for user accounts on computers.
Cryptography was initially used as a secret language shared by members of the military. Throughout the years, and through the progression of computers and information storing devices, the language was adopted by the public. Other instances of modern cryptography include the eCommerce purchases.
The highest level of cryptography is AES encryption, which refers to a multistage cypher. As of 2015, AES is used by the NSA.