LRU, or Least Recetly Used, is one of the Page Replacement Algorithms, in which the system manages a given amount of memory - by making decisions what pages to keep in memory, and which ones to remove when the memory is full.

Huffman Coding is one of the lossless data compression techniques. It assigns variable-length codes to the input characters, based on the frequencies of their occurence. The most frequent character is given the smallest length code.

I came across this image by a Facebook page (Curiosity), which asked a solution to the famous Water Jug problem, involving 3 jugs.