[Wellsita]

Oceania's people are in three classes — (i) the Inner Party, (ii) the Outer Party, and (iii) the Proles. This government, the Party, controls them via the Ministry of Truth (Minitrue), where Winston Smith, the protagonist, works; he is a member of the Outer Party. His job in Minitrue is the continual rewriting and altering of history so that the government is always right and correct: destroying evidence, amending newspaper articles, deleting the existence of people identified as unpersons.


This is part of the explation found in Wikepedia about the book (1984) that inspired Big Brother!