Cryptography is derived from Greek word ‘cryptos’ which mean hidden.

Cryptography is the art of encrypting confidential information and messages before transmitting them to another computer or location and then decrypting them when they reach the intended destination.

In today's modern world hiding confidential information is a vital objective for any organization or country.

When this information needs to be transmitted to another location it becomes vulnerable to hackers and eavesdroppers.

Cryptography presents different methods to make that transition of information from one location to another location secure and safe.

The process is simple yet very secure. First the information is ciphered by the sender.

The sender encrypts that information and generates a key which would be used by the receiver to decipher that information.

After being encrypted that information is send to the sender using what so ever medium that is available.

When the encrypted information reaches its destination it is decrypted using the key provided by sender.

There are four basic objectives of cryptography:

- Confidentiality

- Integrity

- Non Repudiation

- Authentication

There are three basic algorithms that are used in cryptography:

- Secret key cryptography

- Public key cryptography

- Hash functions cryptography