1. Plaintext (اصل Data / Original Message) Plaintext wo normal readable data hota hai jo kisi ne likha ho ya bhejna ho, bina kisi protection k. Example: Agar aap WhatsApp pe likho: "Hello Manan, Meet me at 5pm" – ye plaintext hai. Ye kisi bhi banda easily parh sakta hai. 2. Ciphertext (خفیہ Data / Hidden Message) Ciphertext wo data hota hai jo encrypt (lock) kia gaya hota hai taake koi doosra usay na parh sakay. Example: Agar "Hello Manan" ko encrypt karo to ban sakta hai: "Xlwwr Qfrfr" Ab ye ciphertext hai. Sirf jis k paas key hogi wo isay wapas original me badal sakta hai. 3. Encryption (Lock Karna / Data ko Secure Karna) Encryption ka matlab hota hai plaintext ko ciphertext me badalna – yani data ko lock kar dena. Example: Aapka message: "Meet me at 5pm" Encryption k baad: "Pfhy ph cv 5ro" Ab ye safe hai, koi beech me data churaye to bhi samajh nahi sakta. 4. Decryption (Unlock Karna / Data ko Wapas Readable Banana)...