As a lifelong Episcopalian, I can provide a more in depth answer.
The Church of England
You probably heard that Henry VIII wanted a divorce and the pope would not provide one, so he created his own church, with himself as the head. That's relevant to Anglicans today because with a separate church, the reformation had a different course than in Roman Christendom as a whole. Remember that this is around the same time as Martin Luther was preaching, so at this point many 'protestant' demands were for reform, rather than separation. In the time of Elisabeth and Cromwell in particular, the CofE incorporated many of Luther's reforms while maintaining the tradition of Christianity as it had passed through the years. Archbishop Cranmer wrote the Book of Common Prayer, which managed to incorporate many reformation ideas while translating the rich heritage of the Latin missa (or mass, in English) into the English language. It is this Book of Common Prayer that, in its various revisions, unites all Anglicans in form of worship (although it contains 2 seperate rites [loosely 'services'] for every Sunday and several special occasions with their own language.
The Anglican Communion
As England's colonies, starting with America, broke off from colonial rule, it became impossible for congregants to swear loyalty to the King of England as the head of their church. Without boring you with the way it developed, each country has a national church, which largely is able to determine its own composition and workings. Each national church is divided into dioceses, with a bishop that leads each. In most churches, including the Episcopal church, these Bishops are elected by the dioceses as a whole. The Archbishop of Canterbury is the spiritual leader of the Anglican Communion, but has little real authority over member churches. His power of persuasion, however, has proven to be considerable. The Archbishop of Canterbury every 10 years calls the Lambeth Conference, to which he invites the bishops from all the member churches. Lambeth functions as a sort of congress for enacting Communion business. The title archbishop does not imply authority, but rather is because Canterbury was already an archdiocese when the church was formed. There is also an archbishop of York. When bishops have been bad, they don't get invited to Lambeth. The openly gay bishop of Vermont and several African bishops who accepted defecting churches from America have most recently been left off the guest list.
The Episcopal Church
is the Anglican Communion in America. It is widely different according to each diocese and church, with some prefering more formal services, up to and including big cathedrals, incense, and chanting. It can also be quite austere, or even very modern. The common tie is that we present communion (every sunday in most cases, although that is not universally true) and read an old testament reading, a new testament reading, and a gospel reading. This is prescribed by a 3 year cycle called the lectionary that ensures that the whole bible gets equal attention. Finally, we all say the Nicene Creed and the Lord's Prayer every sunday. It is worth noting that we have a shared communion with the Lutheran Church.
Hope that was useful