What is the two minutes hate?

During the Two Minutes of Hate, Emmanuel Goldstein’s face is shown on the telescreen and horrible screeches are heard in response. There are a number of different feelings and emotions going through people's minds.

"Before the Hate had proceeded for thirty seconds, uncontrollable exclamations of rage were breaking out from half the people in the room. The self-satisfied sheep-like face on the screen, and the terrifying power of the Eurasian army behind it, were too much to be borne: besides, the sight or even the thought of Goldstein produced fear and anger automatically."

Party members channel all their repressed emotions into hate of Goldstein and the forces they perceive are against BB. There is a lot of vitriol, screaming, and cursing at the screen. This propaganda is bizarre as Goldstein's head turns into a bleating sheep but people do not question this very childish way of mocking their enemy.