There was a time when the word "Mechanic" aptly described a profession. Machines that moved by turning chemical energy into kinetic were governed by mechanical contraptions.

The fuel pump was driven by an eccentric on the camshaft. It wasn't located inside the gas tank. Fuel was delivered via linkage between your foot and the throttle plate, not by some form of computer controlled direct injection. Spark was "distributed" by rotating mechanical switches. Spark advance was accomplished by using vacuum to pull a lever. (I dare you to try to find a distributor on a new car.) You knew how fast you were going because a gear was turning a cable plugged into your mechanical speedometer. Power was transmitted to the rear wheels through a set of gears that you selected by depressing a pedal and moving a lever. Now a computer makes those shifts for you via sensors and solenoids.

Gone are the days when you could look at something, take it apart and figure out how it works. I miss the days of the mechanic. There is just something far less personal dealing with machines and their "brains" with their associated sensors, and the programming behind them.

We can't go back because of the gains in gas mileage and pollution control but... think about it the next time you need to have your throttle position sensor replaced.