When someone says 'ray tracing' to me today, before they elaborate on what they mean, I assume they're talking about using straight line segment visibility tests probably to make some kind of picture, probably using Monte Carlo techniques, probably for global illumination. So, they might mean path tracing, or one of the (many) other ways to simulate lighting, or my assumption might be wrong, but that's okay because language is fun, and vague, overridden and imperfect terms allow us to have longer conversations. :)
>The “begetted” eightness as the system-limit number of the nuclear uniqueness of self-regenerative symmetrical growth may well account for the fundamental octave of unique interpermutative integer effects identified as plus one, plus two, plus three, plus four, as the interpermuted effects of the integers one, two, three, and four, respectively; and as minus four, minus three, minus two, minus one, characterizing the integers five, six, seven, and eight, respectively [3].
[1] http://www.ecse.rpi.edu/~wrf/Teaching/graphics-s2005/heckber...
[2] https://wattsupwiththat.files.wordpress.com/2012/01/bg-equat...
[3] Fuller. R.B. Synergetics. MacMillan, New York, 1975,~. 125.