It used to be so simple. If you wanted to record something, you bought a circular or strip chart paper recorder. If there were multiple channels and not a lot of space available, you bought a multi-pen or multi-point recorder. If you happened to work for a utility company, once a year you made some salesman's day when you placed a huge order for chart paper. Of course if you needed to compare what happened in the last hour with what occurred last month and the month before, the solution wasn't very "friendly." Even the wildest guess would probably not come close to estimating the amount of time spent unrolling and re-rolling strip charts over the years. Come to think of it, maybe those "simple solutions" weren't that great after all.
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