What is the origin of the idiom "big brother" and when to use it?

The idiom "big brother" originated from George Orwell's dystopian novel "1984," published in 1949. In the novel, "Big Brother" symbolizes an all-powerful and oppressive government that maintains constant surveillance over its citizens, suppressing individual freedoms and manipulating their thoughts and actions. The character of Big Brother represents the embodiment of a totalitarian regime that exercises complete control and instills a sense of fear and conformity. It is commonly used in discussions about government surveillance, privacy concerns, and the erosion of personal freedoms.