You rarely get to see a 3-digit year in actual use. The photo below shows the date in a document signed by the Holy Roman Emperor Charles III (a.k.a. Charles the Fat) on 2 April 883.
The document can be seen in the Deutsches Historisches Museum in Berlin, Germany.
The text reads:
Data iiii N.APR Anno Incarnat dni dcccLxxxiii Indict i
This means, "The 4th day before Nonae of April in the year of the Incarnation of the Lord 883, Indiction 1."
See the Calendar FAQ for the meaning of Nonae and Indiction.