Questions & Answers
Browse all 20 questions from the
Fundamentals of Cryptography study set below.
Each question shows the correct answer — select a study format above to practice interactively.
1
What is the name of the simple cipher that shifts every letter of the alphabet by a fixed number of positions?
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A
Caesar cipher
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B
Morse code
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C
Binary
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D
Pigpen cipher
2
Which famous method of communication uses dots and dashes to represent letters and numbers?
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A
Braille
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B
Morse code
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C
Hieroglyphics
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D
Semaphore
3
What is the term for a text that has been converted into a secret format to hide its meaning?
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A
Ciphertext
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B
Plaintext
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C
Metadata
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D
Algorithm
4
In the Pigpen cipher, what is used to represent the letters of the alphabet?
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A
Musical notes
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B
Geometric shapes
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C
Animal drawings
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D
Color codes
5
Which machine was famously used by Germany to encrypt messages during World War II?
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A
ENIAC
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B
Enigma
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C
Colossus
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D
Typewriter
6
What is the study and practice of techniques for secure communication called?
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A
Cryptography
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B
Calligraphy
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C
Stenography
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D
Typography
7
Which ancient civilization is credited with using one of the earliest known forms of substitution ciphers?
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A
Romans
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B
Mayans
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C
Vikings
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D
Incas
8
What is 'plaintext' in the context of codes and ciphers?
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A
The encrypted message
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B
The original, readable message
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C
A type of code key
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D
A blank piece of paper
9
Which system uses physical bumps on a page to represent letters for people who are blind?
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A
Morse code
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B
Braille
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C
Semaphore
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D
ASCII
10
In computer science, what are the only two digits used in binary code?
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A
1 and 2
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B
0 and 1
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C
3 and 4
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D
9 and 0
11
What is the secret piece of information used to encrypt or decrypt a message called?
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A
Key
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B
Lock
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C
Password
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D
Signal
12
Which form of communication uses flags held in specific positions to represent letters?
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A
Semaphore
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B
Morse code
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C
Braille
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D
Hieroglyphics
13
What is the process of turning ciphertext back into readable plaintext called?
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A
Encoding
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B
Decoding
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C
Stretching
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D
Formatting
14
Which famous code-breaking center was based in the United Kingdom during World War II?
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A
Bletchley Park
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B
Area 51
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C
The Pentagon
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D
The Louvre
15
What does the acronym 'ASCII' represent in computing?
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A
American Standard Code for Information Interchange
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B
Advanced Secret Cipher for International Intelligence
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C
Automated System for Coding Internal Information
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D
Applied Scientific Code for Internet Interaction
16
What is a 'null cipher' in cryptology?
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A
A code that uses no letters
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B
A message where the hidden meaning is concealed by extra, irrelevant characters
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C
A cipher that cannot be broken
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D
A system that uses only numbers
17
Which historical leader is often associated with the cipher that shifts letters by three positions?
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A
Julius Caesar
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B
Napoleon Bonaparte
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C
Alexander the Great
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D
Genghis Khan
18
What is a 'polyalphabetic' cipher?
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A
A cipher that uses multiple substitution alphabets
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B
A cipher that uses only one alphabet
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C
A code based on numbers only
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D
A message written in multiple languages
19
Which object was used in ancient Greece to wrap parchment around to create a transposition cipher?
-
A
Scytale
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B
Abacus
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C
Astrolabe
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D
Quill
20
What is the main goal of cryptanalysis?
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A
To create secret codes
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B
To break codes without knowing the key
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C
To write messages in code
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D
To invent new languages
