[chc]

Those numbers are of practical importance to programmers in particular. They directly affect nearly everything we do to some degree. On the other hand, without knowing anything about you, I can pretty confidently guess that the identity of Leonidas and the process of tanning leather are not practical concerns for you at all.

Also, I would argue that memorizing those numbers themselves is unimportant and putting too much stock in them is a mistake (some are very likely a bit different on the computer you're working with than they were on the one used to compile the list — for example, hitting L2 cache is slightly faster than a branch misprediction on the i7 IIRC). The important takeaway IMO is the orders of magnitude at work.

[jleader]

If you were developing technical products in 1921, the process of tanning leather was probably very relevant, as were questions about the density of different kinds of wood, the sources and production of various metals, etc.

Just as a programmer should know the orders of magnitude of latencies, an industrial engineer in Edison's time should have a sense of the characteristics of materials he might be choosing between. For example, should the handle of a new tool you're inventing be made of leather-wrapped steel, or hickory (traditionally used for ax handles)?