The whole dispute can be hung on four words of Jesus at the supper: "This is my body." Every Western tradition reads them, and they read them six different ways. The point of this entry is that none of the six is "the Christian view", each is the settled teaching of a major body of Christians, and they are mutually exclusive.
Transubstantiation (Roman Catholic). The bread and wine cease to be bread and wine. Their substance, what they most deeply are, becomes the body and blood of Christ, while the accidents, everything the senses report, remain unchanged. The change is complete at the words of consecration and it lasts, which is why the Catholic Church reserves and adores the host. Trent defined the word in 1551, borrowing Aristotle to state a mystery, not to explain it away.
Sacramental union (Lutheran). Luther kept the realism and threw out the metaphysics. Christ's body and blood are truly present "in, with, and under" bread that stays bread. He would not read "is" as "signifies", at Marburg in 1529 he reportedly chalked hoc est corpus meum on the table and would not be moved. The popular label "consubstantiation" is one Lutherans reject, because it smuggles back the philosophical apparatus Luther refused.
The change as mystery (Orthodox). The East affirms a real change, metabole, brought about above all by the calling-down of the Spirit, the epiclesis. But it declines to say how, and regards the Western itch to specify the mechanism, whether by Aristotle or against him, as the actual error. The affirmation is as strong as Rome's; the refusal to dissect it is the difference.
Real presence, mode undefined (Anglican). The Church of England says Christ is truly present and truly received, and then, deliberately, stops. Article 28 rejects transubstantiation by name as "repugnant to the plain words of Scripture," but the tradition holds together those who mean by "real presence" something nearly Catholic and those who mean something nearly Calvinist. The reticence is the doctrine.
Spiritual real presence (Reformed). Calvin refused both Rome and Zurich. The supper is no bare memorial: Christ is truly given and truly fed upon. But the presence is not local, Christ's body is in heaven, and the feeding is the work of the Holy Spirit, who lifts the believer to Christ rather than bringing Christ down into the bread. Faith receives; the mouth does not.
Memorial (Baptist, Anabaptist, most evangelical). Zwingli read "is" as "signifies." The supper remembers and proclaims a sacrifice finished once on the cross; the bread and wine are signs that point, and Christ is present in the gathered church and by the Spirit, not in the elements. This is now the majority view across the free-church and evangelical world.
The Marburg Colloquy of 1529 is the moment the divisions set. Luther and Zwingli agreed on fourteen articles and broke on the fifteenth, the supper. They parted without communion between them, and the Protestant world has never fully closed the gap that opened over those four words.