> If Ogham is inefficient to use in
> conveying information, then why are bar codes efficient? Is it because
> a machine can read them more readily?
I would think so, yes. Correct me if I'm wrong, but to my knowledge the relevant feature in bar codes is the thickness of the bar. That is to say, the bars of bar codes carry
a single piece of information, namely their thickness which gives the reading machine the one information it needs. Bar codes are not redundant.
The human mind and the human cognitive system work differently. Human encoding systems (writing systems, spoken languages, signs etc.) overflow in redundancy.
Viewed from that perspective, the Ogam script is much closer to bar codes in that it is almost a non-redunant writing system.
> I suspect that Ogham is merely
> inconvenient because most of us have little practice in using it.
That may be true. But its near non-redundancy makes it very vulnerable to errors. If a single stroke is lost - for whatever reasons - it conveys wrong information whereas for
example the letter "A" would still be recognisable if one of its strokes was lost.