bpc = bits per component
For RGB, you usually have 8bpc for each of the red, green, and blue components.
5bpc = 15 bit color = thousands of colors (32,768 colors)
5bits for red and blue, 6 bits for green = 16 bit color = thousands of colors (65,536 colors)
8bpc = 24 bit color = millions of colors (16,777,216 colors)
10bpc = 30 bit color = billions of colors (1,073,741,824 colors)
12bpc = 36 bit color = billions of colors (68,719,476,736 colors)
14bpc = 42 bit color = trillions of colors (4,398,046,511,104 colors)
16bpc = 48 bit color = trillions of colors (281,474,976,710,656 colors)
For Y'CbCr the components are the luma component, and the blue-difference and red-difference chroma components. Chroma subsampling might be used (instead of 4:4:4, use 4:2:2 or 4:2:0) to reduce bandwidth - this means that while every pixel can have a different Y', only every 2nd pixel and/or every 2nd line can have different chroma (CbCr).
Maybe. Maybe the new Mac Pro. Maybe the new Apple Thunderbolt display to go with the new Mac Pro. Maybe the new Thunderbolt display will support the new USB-C input feature of Titan Ridge to also support computers that don't have Thunderbolt.