Human Visual System (HVS)

Optics

Cornea [Hornhaut]
Iris [Iris], cf. f-stop setting [Blendeneinstellung] of a camera
Pupil [Pupille], a hole, not an actual part
Lense [Linse]
Vitreous body [Glaskörper]
Retina [Netzhaut], cf. red-eye effect on flash photographs
Optic nerve [Sehnerv]

Receptors

Spatial distribution of light, spectral distribution of light
100 million rod cells [Stäbchenzellen] for night vision. They can detect single photons, but produce only a grey-scale image. Night vision does not constitute a mainstream topic of computer graphics
6 million cone cells [Zapfenzellen] for daylight vision

Three different types for three primary colors [Grundfarben]: red (long wavelength, L type), green (medium wavelength, M type), blue (short wavelength, S type)
Blue-sensitive cones are much less abundant than the other two types (1/40 of red). Hence, low spatial resolution for images composed of blue and black.
Color-to-grayscale conversion: green is most important, blue least. Typical weights are approximately 0.3*red + 0.6*green + 0.1*blue (demo with Photoshop).
Red-green color blindness: due to a genetic defect, red and green cone cells are identical (demo with Photoshop).

Color Mixing, Color Spaces

Additive mixing [additive Farbmischung]: Start from black and switch on lights: green + blue = cyan, blue + red = magenta, red + green = yellow (somewhat surprising), equal parts of red + green + blue = grey or white. (demo with Photoshop)
There can be a bluish green but no bluish yellow etc.
Color naming anomaly: There is no dark shade of yellow. (demo with Photoshop)
In printing, we subtract color (hence subtractive mixing) from paper white. RGB as primary colors for a printer won't allow mixing. We rather use cyan (absorbs red = long wavelengths), magenta (absorbs green), and yellow (absorbs blue). Y+M=R, Y+C=G, C+M=B (only theoretically; with existing printing colors it's violet), equal parts of C+M+Y = grey or black (only theoretically; in practice it's brownish and never becomes really dark). In practice, black is almost always used in addition to CMY. (demo with Photoshop)
Physics views color as a distribution of power over the spectrum of visible light (short/medium/long wavelengths), corresponding to MRYGCBM, the colors of the rainbow. Humans, however, think of color in terms of the color wheel [Farbkreis] with parameters such as Hue [Farbton], Saturation [Sättigung], and Brightness [Helligkeit]. There are some simple methods (such as HSV and HSL) to map these parameters to RGB and some sophisticated methods (such as Lab, which officially is called L*a*b*) that are based on experiments. (demo with Photoshop)
Most display devices [Anzeigegeräte] behave in a non-linear manner. RGB = (255, 255, 255) will typically be about four times as bright as RGB = (127, 127, 127). This relationship is represented through a power law [Potenzgesetz]

The color of a glowing piece of material of a certain temperature can be used as a reference for some colors. Temperature is measured in Kelvin, which is degrees Centigrade [Grad Celsius] plus 273. Standard light bulbs have a color temperature of about 2,000 to 3,000 Kelvin. Sunlight on a clear day is around 6,500 Kelvin, with overcast sky 8,000or more Kelvin. Note that a heated material glows red, yellow and blue (yes, blue!) with increasing temperature.

Built-In "Intelligence" and Visual Illusions

There are no receptor cells where the optic nerve connects to the retina. This "blind spot" [blinder Fleck] is hidden from consciousness. (experiment)
Only the Fovea [gelber Fleck], a small central region of the retina, contains a large concentration of cone cells. Only here, daylight (i.e., color) vision yields sharp images (experiment). To compensate for that, the eye scans the focused object with small leaps (saccades). We perceive the illusion of a completely sharp image.
Color balance [Weißabgleich]: Color perception adapts to the color of the light. For instance, we perceive a sheet of paper as white even when it is lit by a candle.
3D vision = perception of depth: to be covered later
Visual illusions: In uncommon situations, the built-in intelligence may fail. (demonstrations)

Content Types and File Formats of Computer Graphics

	static	animated	interactive
2D	bitmap, vector graphics, font	motion picture, animated vector graphics	graphical user interface (GUI), Web site
3D	static 3D scene	animated 3D scene	virtual reality (VR)

So-called "3D" computer graphics is mostly concerned with producing 2D images or films from 3D descriptions.

Some examples for file formats:

BMP: 2D bitmap, typically RGB with one byte per color channel and no compression
JPG: 2D bitmap, compressed with loss
EPS: vector graphics expressed in the printer-oriented programming language PostScript
OBJ: geometry data of 3D polygon objects (and seldom other types of objects)