 Cardinality, [1]
 Carmichael number, [1]
 Cell
 Certificate, [1]
 Chain rule
 Chebyshev's inequality, [1], [2]
 Chernoff bounding technique, [1]
 Chernoff bounds, [1], [2]

ChernoffHoeffding bounds

see Hoeffding's inequality
 Chomsky hierarchy
 ChurchTuring thesis, [1]
 Ciphertext
 Circuit satisfiability
 Classical computer
 Clause, [1]
 Clique, [1]
 CLIQUE (language), [1]
 Closed
 Closestpair problem

CNF

see Conjunctive normal form
 Corecognizable
 Complement
 Complete graph, [1]
 Completeness

Complexity
 Complexity class

 Compression
 Computable function
 Computational security, [1]
 Computational step
 Concentration bounds, [1], [2]
 Conditional probability, [1]
 Conditional security
 Confidence level
 Confidentiality, [1]
 Configuration, [1]
 Congruence
 Conjunctive normal form, [1]
 Connected
 coNP
 Contextfree language
 Contextsensitive language
 Convex function
 CookLevin theorem
 Coprime, [1], [2], [3]
 coRP (complexity class)
 Countable
 Countably infinite

Cover
 Coverandremove algorithm

Crossing edge
 Cryptography
 asymmetric
 ciphertext
 DiffieHellman, [1], [2], [3]
 DiffieHellman assumption, [1]
 discrete logarithm assumption, [1]
 ElGamal
 factorization hardness assumption
 Kerckhoff's principle, [1]
 key
 key exchange, [1]
 onetime pad
 padding, [1]
 plaintext
 postquantum
 private key, [1], [2], [3]
 public key, [1], [2], [3]
 publickey cryptosystem
 RSA
 RSA assumption
 RSA encryption
 RSA signature
 spoofing
 statistical attack
 symmetric, [1]
 Cut
 Cycle
