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Cryptography is the way of converting a plain text into ciphertext using encryption method and again converting the ciphertext into plain text using decryption method.
Plain text is a normal message which can be read and understood by anyone whereas a ciphertext is the text which can be read by anyone but can not be understood the meaning of it.
Encryption is the method by which information is converted into secret code that hides the true meaning of the information. The conversion of encrypted data into its original form is known as decryption. The science of encryption and decryption is known as cryptography.
We use cryptography because of the reason for securely transmitting and storing information in a way that only authorized individuals can access and understand it. It involves using mathematical algorithms and techniques to encrypt (scramble) data and decrypt (unscramble) it when needed. Cryptography is an old technique which has become popular these days due to cryptocurrency.Read More
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Why do we need to use cryptography?
Cryptography plays a crucial role in protecting data, ensuring privacy, and establishing trust in digital communication, transactions, and systems.It plays a crucial role in ensuring the confidentiality, integrity, and authenticity of sensitive information.
We use cryptography for several reasons:
Secure communication: All the computers, apps, mobiles and systems are vulnerable connected to the internet and the internet is an insecure channel which is available for everyone. If we are sending a message to someone which can be sensitive also including our bank account numbers, passwords etc and someone who has a knowledge of hacking can trace, read and use the information we are sending. If we want our message not to be understood by anyone then cryptography comes to rescue.
Confidentiality: Cryptography helps protect sensitive information by encrypting it, making it unreadable to unauthorized individuals. Only those with the correct decryption key(password) can access the original message or data.
Integrity: Cryptographic techniques ensure that data remains unharmed and unchanged during transmission or storage.
Authentication: Cryptography verifies the identity of individuals or entities involved in a communication or transaction. It ensures that the sender and receiver can trust each other’s identities and that messages are not tampered with by unauthorized parties.
Non-repudiation: Cryptographic mechanisms provide evidence that a particular message or transaction occurred and that the involved parties cannot deny their participation. This helps in establishing accountability and resolving disputes.
How does cryptography work in real life?
Secret Messages:Imagine you have a letter that you want to send to your friend, but you don’t want anyone else to be able to read it. You could use a simple substitution cipher, where each letter in the alphabet is replaced by a different letter. For example, you could shift each letter three positions to the right. So, “A” becomes “D,” “B” becomes “E,” and so on. Your message “HELLO” would become “KHOOR” using this cipher.Now, you send the encrypted message to your friend. Even if someone intercepts it, they would only see a jumble of letters, and it would be difficult for them to understand the original message without knowing the cipher. This way, your message becomes jumbled and looks like nonsense to others. Only your friend, who knows the code, can decipher it and read your original message . When your friend receives the message, they can use the same cipher to shift each letter three positions to the left and decrypt the message back to “HELLO.”
Password Protection: When you create an online account, you choose a password to secure it. Websites don’t store your password as it is because that would be risky if their database gets hacked. Instead, they use cryptography to convert your password into a unique code. Even a small change in the password creates a completely different code. So, if a hacker gets hold of codes, they can’t figure out your actual password.
Secure Communication: When you send sensitive information online, like banking details or private messages, it needs protection. Cryptography comes into play by encrypting your information. Encryption turns your data into a jumble of characters using complex math. Without the decryption key, it’s practically impossible for anyone to understand the original information.
Digital Signatures: Digital signatures ensure the authenticity and integrity of electronic documents. When you digitally sign a document, you use a special key to create a unique code based on the document’s contents. This code acts like a digital fingerprint, proving that the document hasn’t been tampered with and that it came from you.
Secure Online Shopping: Cryptography is crucial for safe online transactions. When you make a purchase online, you enter your credit card details. To protect this information, secure websites use encryption protocols like SSL/TLS. This encrypts your credit card data during transmission, making it extremely difficult for attackers to steal and misuse it.
