Law of Unintended Consequences
Every action has a predicted consequence — along with side-effects the actor did not dream of (see wikipedia). A few examples:
- Railroads forced the creation of a national time-table. Previously, cities kept their own time. New York and Philadelphia could be 5 minutes off, for example, which would disrupt train schedules.
- The car gave rise to the current popularity of …
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Math & Numbers
- Mental math shortcuts, adding 1-100
- Understanding exponents and the natural log
- Div, Curl, Flux, Gradient and other Vector Calculus topics
Programming & Web Development
- Site speedups with HTTP caching, gzip compression
- Understanding Rails, Web debugging, and Javascrtipt
- Swap bytes with XOR, byte order, unicode
