Cryptology is a science that studies everything that has to do with codes and passwords.
Cryptography's primary objective is data protection. Encryption, in simple terms, is converting data into an "unreadable" form.It provides solutions for four different security areas:
Privacy/confidentiality: Ensuring that no one can read the message except the intended receiver.
Authentication: The process of proving one's identity.
Integrity: Assuring the receiver that the received message has not been altered in any way from the original.
Control: A mechanism to prove that the sender really sent this message.
In everyday society, we see many forms of data protection. The most obvious include PIN numbers, Social Security numbers and passwords for such things as email. Everyday, people recognise the need for security and the need for data protection.
Cryptography dates as far back as 1900 BC when a scribe in Egypt first used a derivation of the standard hieroglyphics of the day to communicate. A more familiar example of an historical use of cryptography would be the morse code.
However, with the recent explosion of technology (such as the internet
), the vulnerability of personal information has increased. In accordance with this, there is a far greater need for better methods of data encryption. Modern cryptography has lead to complex computer algorithms
which have been written to allow for far more secure and protected data. Even for everyday passwords, the algorithms can be highly sophisticated, I've included this link which shows what an algorithm looks like: garykessler.net/library/crypto.html#password.
Quantum cryptography is an effort to allow two users of a common communication channel to create a body of shared and secret information. This information, which generally takes the form of a random string of bits, can then be used as a conventional secret key for secure communication.
The advantage of quantum cryptography over traditional key exchange methods is that the exchange of information can be shown to be secure in a very strong sense, without making assumptions about the intractability of certain mathematical problems. Even when assuming hypothetical eavesdroppers with unlimited computing power, the laws of physics guarantee (probabilistically) that the secret key exchange will be secure.