There are only two hard things in Computer Science: cache invalidation and naming things. -- Phil Karlton Long a favorite saying of mine, one for which I couldn't find a satisfactory URL. Like many good phrases, it's had a host of riffs on it. A few of them I feel are worth adding to the page There are 2 hard problems in computer science: cache invalidation, naming things, and off-by-1 errors. --
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