text: In computer jargon, blinkenlights are diagnostic lights on front panels of old mainframe computers. More recently the term applies to status lights of modern network hardware (modems, network hubs, etc.). Blinkenlights disappeared from more recent computers for a number of reasons, the most important being the fact that with faster CPUs a human can no longer interpret the processes in the computer on the fly. Though more sophisticated UI mechanisms have since been developed, blinkenlights may still be present as additional status indicators and familiar skeuomorphs.
  Etymology
  The term has its origins in hacker humor and is taken from a famous (often blackletter-Gothic) mock warning sign written in a mangled form of German. Variants of the sign were relatively common in computer rooms in English-speaking countries from the early 1960s. One version read:
  Some versions of the sign end with the word blinkenlights.