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CMY can make a real black, inability to make a good black is not the main reason that the K seperation is added. Screening a good black is difficult due to the non-linear way you see color, however. See below.

From the Color FAQ

BTW - I highly recommend the Color FAQ as a good primer.

25. Why does offset printing use black ink in addition to CMY?

Printing black by overlaying cyan, yellow and magenta ink in offset printing has three major problems. First, coloured ink is expensive. Replacing coloured ink by black ink - which is primarily carbon - makes economic sense. Second, printing three ink layers causes the printed paper to become quite wet. If three inks can be replaced by one, the ink will dry more quickly, the press can be run faster, and the job will be less expensive. Third, if black is printed by combining three inks, and mechanical tolerances cause the three inks to be printed slightly out of register, then black edges will suffer coloured tinges. Vision is most demanding of spatial detail in black and white areas. Printing black with a single ink minimizes the visibility of registration errors.

Other printing processes may or may not be subject to similar constraints.

Digital images aren't distorted, they just don't fit our colour perception. (AFAIK, among others, more a logarithmic scale in contrast to the linear used in digital images)
Actually, nonlinear storage/transmission of colour intensity is quite common (aka gamma). TVs use it and most computer systems do too. For a very good description of this field try Charles Poynton's Colour and Gamma FAQs

Charles Poynton maintains an excellent FAQ for color and gamma related questions, that is infrequenctly posted to comp.graphics.algorithms. You can get it online here: http://www.inforamp.net/~poynton/ColorFAQ.html

CIE XYZ is not a perceptually-uniform space. Use CIE LUV instead.

Color comparison (even on a monitor) is a hairy topic, and depends a lot on your monitor, how far you are from it, gamma correction, and so on --- these wacky subtleties can influence the perceived accuracy of your comparison.

Here is what you should have read instead of posting this question:
Color FAQ (see Question 34, "What is perceptual uniformity").

• The CIE color space: A pretty decent introduction to what the CIE color space is
• Color FAQ: I haven't read through this, but it seems to be a more extensive coverage of color and how it's much more than RGB, HSV, or CYMK.

I also bought one of the tiny little ones, and still use it. Mine is labelled as per the subject line even though it doesn't have a Z-80 in it, and the keyboard layout is a little different than yours: see a picture of it here. According to that page, mine was introduced in 1980, but I bought it in 1983 when the line was discontinued for the whopping price of $CAD 65 (including the soft case and cassette interface).

Yes, I lusted after a Model 100 when they came out (this is what they looked like if you've never seen one...) but I ended up buying the even more useful Tandy PC-2 pocket computer. It was amazing how many Physics and Chemistry equations you could store in 3.5K. Never would have made it through the core curriculum in college without my artificial memory...;)

I'm not entirely sure what driver's liscences look like in the states right now, but here in Ontario we already have . We also have health cards(for the national health care system that us socialists have) that look identical to the drivers licenses, only they're green.

All cops have a little computer in their cars where they can swipe your lisence and bring up your criminal and civil record. It's gotten to the point now where some dance clubs swipe licenses in order to check ID for age. There is already significant talk of uniting both of these card into a one piece that also contains the Social Insurance Number(Social Security for you americans).

Anyways my point is that this all managed to slip under the radar in Ontario about five years back and there was almost no public resistance to it(probably because the old two-piece driver's lisence was so damn ugly and inconvenient), and there is almost no public knowledge as to what kind of information is actually stored on that magnetic strip.

Don't let it happen if you can avoid it.

How should I adjust my monitor's black level and picture controls?
On a CRT monitor, the picture control, often misleadingly labelled contrast, adjusts overall luminance. The black level control, often misleadingly labelled brightness, adjusts offset. Display a picture that is predominantly black. Adjust black level so that the monitor reproduces true black on the screen, just at the threshold where it is not so far down as to "swallow" codes greater than the black code, but not so high that the picture sits on a pedestal of dark grey. When the critical point is reached, put a piece of tape over the black level control. Then set picture to suit your preference for display luminance.

In fact, JPEG relies on perceptual coding, so that the perceived effect of the lossy algorithm is minimized.

The exceptions to the rule are SGI machines (which were designed with ray-tracing in mind, so they assume physical coding in the frame buffer and use gamma correction to convert to perceptual coding) and Macs (which have a gamma correction intended to mimic the dot gain of the original Laser Writer.)

For more than you ever wanted to know about gamma, see Charles Poynton's Gamma FAQ and the sRGB proposal.

Reducing eyestrain from video and computer monitors
Charles Poynton

"Black Level" and "Picture"

Reducing eyestrain from video and computer monitors
Charles Poynton

"Black Level" and "Picture"