'Protestant' in this context is basically Lutheranism, plus I supposed the Church of England.
'Reformed' is Calvinism.
Luther was originally a priest, monk and university professor. A big part of his agenda was to reform the worldly corruptions of the late Medieval & Rennaissance Catholic Church, but since they declared him a heretic he had to form a new one. The key beliefs were 'Priesthood of the believers' (clergy are just those who choose to serve fellow Christians, you don't need to recieve sacrements from a specially ordained priest to get to Heaven as taught by Catholic & Orthodox), no source of religious authority but the bible (as opposed to the Pope for Catholics, councils of bishops for Orthodox), and salvation through faith & grace alone (as opposed to any 'works' you do or any clergy does in your name). However, if you attend a Lutheran service the minister is still in robes and chants parts of the service, etc... not unlike a Catholic service.
The Church of England was pretty much the same, except even closer to Catholic in the service and they kept Bishops & the Apostolic Succession (meaning Jesus laid hands on the Apostles, who laid hands on the first generation of Bishops, so on down through today - and Priests have to get ordained by Bishops and you have to recieve sacrements from ordained priests to get to heaven).
John Calvin (Jean Calvin in EU) was lawyer and built on the above, but took a very legalistic look at interpreting the bible. The 'Puritans' and 'Separatists' (like the 'Pilgrims' at Plymouth Rock) were Calvinists. Calvinist services were described as 'four bare walls and a sermon' - no robes, no religious art, no chanting or other 'Popery'. Emphasis was on the majesty and power of God, not on God's love for mankind. One key belief was that since God is all powerful and nothing happens except by His will, then at the beginning of time He 'preordained' who would be saved and who would not. If you are preordained to be saved, you are one of the 'Elect' and won't be able to avoid being a good (Calvinist) Christian. Otherwise, you are toast regardless of your faith or lack thereof. Calvinists tended to be very militant.