Substitution vs transposition ciphers | classical encryption techniques | Cryptography | Urdu/Hindi

Substitution ciphers in general, some of them keeping one or multiple letters the same. a type of substitution cipher in which each letter in the plaintext is replaced by a letter with a fixed number of positions down the alphabet. In other words, a Caesar Cipher is a simple special case of a substitution cipher. In transposition cipher, a simple example is columnar transposition cipher where each character in the plain text is written horizontally with specified alphabet width. Now, the receiver has to use the same table to decrypt the ciphertext to plain text.