Strange quark
The first strange particle (a particle containing a strange quark) was discovered in 1947 (kaons), but the existence of the strange quark itself (and that of the up and down quarks) was only postulated in 1964 by Murray Gell-Mann and George Zweig to explain the Eightfold Way classification scheme of hadrons. The first evidence for the existence of quarks came in 1968, in deep inelastic scattering experiments at the Stanford Linear Accelerator Center. These experiments confirmed the existence of up and down quarks, and by extension, strange quarks, as they were required to explain the Eightfold Way.
Quantum chromodynamics
QCD exhibits two main properties:Physicist Murray Gell-Mann (b. 1929) coined the word "quark" in its present sense. It originally comes from the phrase "Three quarks for Muster Mark" in "Finnegans Wake" by James Joyce. On June 27, 1978, Gell-Mann wrote a private letter to the editor of the "Oxford English Dictionary", in which he related that he had been influenced by Joyce's words: "The allusion to three quarks seemed perfect." (Originally, only three quarks had been discovered.)