Problem – Error – Report

The field broken things is fully of confusing terminology. When I say something, it means precisely what I mean it to say, so here are some definitions of terms. Keep these straight and you’ll be half-way there.

I use the word problem here to mean, “The cause that made the system produce errors.”

A Problem could be

• A Fault
  Something that is broken or worn out, that is repaired by replacing the broken part
• An out-of-calibration event
  Something that is repaired by making an adjustment (like putting more air in a tyre if the pressure is low)
• A design flaw
  Something that is fixed by changing the design
• An upset
  Something that goes wrong, but isn’t evidence that the system is breaking down. The cosmic-ray-induced soft errors in computer memory are an example of an upset. Provided they don’t happen too often, we just learn to live with them.
• and other stuff

so ‘problem’ covers all sorts of causes. We tend to give different names to the causes depending on what action we need to take to make the system work properly. But, all these different sorts of problem share the fact that they cause the system to produce errors rather than working properly.

I use the word error here very carefully, too.

An Error is

• A signal or datum that is wrong.
  For example, low air pressure in the tyres, high temperature in the engine, zero RPM when the engine is supposed to be running.

An error is internal to the system. It might propagate within the system and cause more errors. For example, low tyre pressure might cause tyre overheating. However, we won’t notice anything is wrong (we’ll be under the misapprehension that the system is working properly) until the error is detected by some error detector and produces a report.

A Report is

• The output of an error detector that says “There’s an error!”
  For example, the warning light that tells that the engine is overheating
• The result of a specific test
  For example, when you measure the tyre pressure and find it is low
• Some human error detector
  For example, you notice the smell of burning rubber.
• Anything else that causes the procedure of diagnosis and repair to start.