The Knobs
The LINC included a set of eight ten-turn potentiometers (numbered 0-7) that could be each be read by a computer instruction. The knobs were a convenient user input device at a time before general adoption of the mouse. For example, the scaling of a displayed graph could be controlled by turning Knob 0. Or Knob 2 could be used to position a cursor in the graph in order to display the actual data value at that point.
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