what is cryptography?

what is cryptography??

Cryptography is a method of converting or protecting our data or message into secret form so that it could not be in wrong hands.The only person which has the key only can read the message.
The cryptography word is made of two words : -crypt and graphy.
Crypt means hidden or vault and graphy means writing so that cryptography means that's the writing or message which is in hidden form.
In cryptography we encrypt(convert our message into secret form) our message in secret form using different cryptography algorithm so that unautorised person could not read the message.
After doing encryption we send data to receiver and in receiver already have a decription key so receiver decrypt(retrieve encrypt data in real form ) the message so that only receiver can read that message.

Objectives of Cryptography :-

1 : Confidentiality :  Confidentiality means that the message will not be reached in hands of unauthorized person.Only the authorized person have to read or receive message.

2 : Integrity : Integrity means that the data which we send will only reached to the receiver,there has no third one interrupt in the data.

3: Authentication : Authentication means that sender and receiver firstly identify each other and then perform the transmission of data.