Almost all non-Catholic Christians are Protestants. There are many factions of Protestantism, such as baptists, Lutherans, etc... The thing they all have in common is they do not believe in the divine authority of the Pope.
I don't think that Witnesses or Mormons would qualify as protestants but they are technically Christians.
protestantism is a form of Christianity which does not agree in Catholicism, protestants believe in salvation through God and not through church fathers or popes, protestants worship Jesus, while catholics worship Mary, protestants want to go with the bible literally