Fussy semantic quibble about digital vs analog
The basic D vs A opposition is almost always misleading. It doesn't match the real distinction between ways of thinking.

Strictly, digital simply means on/off, and analog simply means continuous. Integer vs rational.

BUT: Many familiar digital and analog systems are a complete mix of the two modes.

Example 1: A light switch is strictly digital. It's designed to be either perfectly conducting or perfectly insulating, with as little time as possible between the two extremes. But it controls a light bulb which is strictly analog. An incandescent bulb starts to glow as soon as any current flows, and its light output rises smoothly (but not linearly) with increasing current. An LED lamp is mostly analog, with an area of zero conduction near zero voltage. Fluorescent is closer to digital, requiring a high initial voltage to start, but still varies with voltage after it starts.

Example 2: A thermostat on a heating system or electric stove is an analog knob or slider, controlling the pulse width of a strictly digital system. The burner itself is either all on or all off.

The important distinction is not on/off vs gradual.

The real distinction is digital software versus all other types of systems.

Digital software operates in a series of discrete snapshots of time, and operates in only one direction. There is never any actual feedback in a software system, and there is never any actual motion. Software CANNOT represent reality no matter how fast or powerful the CPU, no matter how many cores or threads are running in parallel. The boundary is perfectly unbridgeable.

It's hard to express this distinction accurately because the precise wording is syntactically clumsy.

So: When I say digital, I mean software, and when I say analog, I mean non-software, which generally includes both on/off and gradual elements.

Labels: Language update

  ¶ 6:50 AM