Lutheran: They follow the theology of Martin Luther. They believe in the 5 Solae: we are saved by grace alone, through faith alone, on the basis of the Bible alone, and glory is given to God alone by the mediation of Jesus alone.
Reformed (Calvinist): They follow the theology of John Calvin. They believe in the principles of TULIP: we cannot seek God by our own will, all the saved are chosen by God from eternity for salvation and all the condemned are chosen by God from eternity for condemnation, Jesus died on the cross for the saved, not for everyone, the grace of God is stronger than the desire of the saved to reject the gospel, and those who are called for salvation will definitely be saved: if one ends up not being saved, they never had true faith to begin with.
Anglican: The historical Church of England which has separated from the Church of Rome and then taken onto Protestant doctrine. Today they are a bit all over the place - you have high-church Anglicans who are practically Catholics without a Pope, and low-church Anglicans who are nearly impossible to distinguish from your average Baptist church. But two important and generally universal documents are the Book of Common Prayer and the 39 Articles.
Methodist: They broke away from the Anglican Church and follow the theology of John Wesley. They reject the more Reformed elements of Anglican theology, and believe that doctrinal authority lays in 4 sources: the Bible, tradition, reason, and experience.
Baptist: They generally believe that there are no sacraments (means by which one has real and immediate communion with Jesus through matter, and receives His saving grace this way), but rather ordinances (rituals that we must do in memory of Jesus because He told us to). As such, they believe that baptism of infants has no effect, but one must be able to confess their faith in Jesus to be properly baptized - and even then baptism does not make an inward change, but rather is an outward expression of the change that has already happened inward. Also, because the eucharist is not really a sacrament, it is of course not really the Body and Blood of Jesus. That aside, Baptists are a bit all over the place too.
Anabaptist: They tend to have a very practical, non-mystical view of sacraments, and so they too believe that the baptism of infants isn't valid. They see the primary purpose of the eucharist as being to express the fraternal communion between the believers. They generally believe in absolute non-violence, and do not swear oaths. It's a bit difficult to discuss them because they don't really have some kind of systematized theology.
Pentecostal: They believe there are three baptisms: baptism into the Body of Christ (which happens through faith), baptism in water (which is an outward expression of the inward change), and baptism in the Holy Spirit (which is given to a truly repentant and faithful heart). Baptism in the Holy Spirit leads to evidence that one has the Holy Spirit, because one receives gifts of the Holy Spirit (speaking in tongues, healing others, becoming fully dedicated to preaching…), and this is proof of salvation.
Seventh-Day Adventist: They follow the theology of Ellen White, whom they also believe was a prophet. Some of their beliefs that are unusual among Protestants: they believe (as dogma) that the world was made in six 24-hour long days. There is no separation betwee the body and the soul, but when man dies he remains unconscious until the resurrection, and at the resurrection those who are condemned will completely cease to exist. They follow the Law of Moses, including the Sabbath, and they worship on Saturday rather than Sunday. They believe that at Jesus's second coming, the saints will be resurrected and reign with Him in heaven while the earth is desolate and inhabited by the demons, then 1000 years later the wicked will be resurrected and destroyed with the demons.
Beside these, you have 2 movements in Protestantism that spread over several denominations (and even beginning to spread into Catholicism):
- Evangelicaism: A stronger focus on spreading the gospel, studying the Bible, and letting other know they can have proof of their eternal salvation.
- Charismaticism: A stronger focus on praying to ask for the Holy Spirit, and on spiritual gifts (most commonly glossalia, that is, speaking in angelic tongues).