Poka-Yoke - designing systems and products in ways to make errors difficult or impossible. For example, with the old 3 1/2" floppy disks you could not but them into the disk drive upside down - see example. Data entry is another potential source of errors - one way to reduce those errors to choose from a selection list rather than typing in data (for example, select the state from a list of states rather than typing in the state name).
Poka Yoke can take the form of prevention or detection (making it obvious that an error has been made so it can be corrected).
Shigeo Shingo is credited with developing poka-yoke into its own area of study in the early 1960's while an industrial engineer at Toyota Motor Corporation. Poka Yoke is a great example of looking for systemic solutions rather than blaming people for errors. The first place to look for why errors happen is the system. Why is it possible for such an error to be made?