Collision attacks try to find two inputs producing the same
https://en.wikipedia.org/wiki/Collision_attack
A collision attack on a cryptographic hash tries to find two inputs producing the same hash value, i.e. a hash collision. This is in contrast to a preimage attack where a specific target hash value is specified.

RSA
https://en.wikipedia.org/wiki/RSA_(cryptosystem)
RSA (Rivest-Shamir-Adleman) is a public-key cryptosystem that is widely used for secure data transmission. It is also one of the oldest. The acronym RSA comes from the surnames of Ron Rivest, Adi Shamir, and Leonard Adleman, who publicly described the algorithm in 1977.

Decoding
Decoding - reverse process from encoding,converting the encoded message back into its plaintext format.

Hashing algorithm
https://en.wikipedia.org/wiki/MD5
The MD5 message-digest algorithm is a widely used hash function producing a 128-bit hash value. Although MD5 was initially designed to be used as a cryptographic hash function, it has been found to suffer from extensive vulnerabilities. It can still be used as a checksum to verify data integrity, but only against unintentional corruption. It remains suitable for other non-cryptographic purposes, for example for determining the partition for a particular key in a partitioned database.

Raw Quick Pair
https://www.cs.auckland.ac.nz/courses/compsci725s2c/archive/termpapers/yy.pdf Du and Long2 (2000) introduced Raw Quick Pairs detecting method of Stego-images (the images that contain the steganographic message). The underlying principle of the method is that the number of close color pairs of Stego-images will be larger compare with the number of close color pairs of normal images. In contrast, Fridrich and Goljan (2001) pointed out that RQP method only works if the number of unique colors is relatively low; and the method can not be applied to grayscale images. However, this paper will outline the core principle of RQP method; and evaluate such critical comments in details. In addition, this paper suggests potential improvement of RQP method and provides one possible alternative.
Incorrect answers:
Chi squared analysis - https://en.wikipedia.org/wiki/Chi-squared_test
Differential Analysis - https://en.wikipedia.org/wiki/Differential_cryptanalysis Discrete Cosine Transform - https://en.wikipedia.org/wiki/Discrete_cosine_transform