COMPUTER FUNDAMENTALS

Detailed explanation-1: -In cryptography, frequency analysis is the study of the frequency of letters or groups of letters in a ciphertext. The method is used as an aid to breaking substitution ciphers (e.g. mono-alphabetic substitution cipher, Caesar shift cipher, Vatsyayana cipher).

Detailed explanation-2: -Frequency analysis for simple substitution ciphers. In a simple substitution cipher, each letter of the plaintext is replaced with another, and any particular letter in the plaintext will always be transformed into the same letter in the ciphertext.

Detailed explanation-3: -Frequency analysis is the study of the distribution (and count) of the letters in a text. Analysis of frequencies helps cryptanalysis and decrypting substitution-based ciphers using the fact that some letters apparitions are varying in a given language: in english, letters E, T or A are common while Z or Q are rare.