Every Reformation Bible in this collection descends from a book printed in Basel in 1516. Erasmus of Rotterdam had wanted to put the Greek New Testament into print before anyone else did, and he worked fast — from the handful of late manuscripts he could reach in Basel, none of them especially old. Where his copy of Revelation was missing its final leaf, he translated the last six verses back into Greek out of the Latin Vulgate. Those verses entered print, and stayed there for four centuries.
The text was corrected and reissued for a hundred years afterwards — by Erasmus himself, then by Robert Estienne in Paris and Theodore Beza in Geneva. Estienne's fourth edition, of 1551, did something with consequences far beyond scholarship: it broke the text into numbered verses. Those are the verse numbers still printed in almost every Bible in the world, and the ones this reader lets you switch off.
The name came last, and it came from marketing. In 1633 the Elzevir brothers of Leiden advertised their edition with the line that the reader now had “the text received by all” — textus receptus. It was a bookseller's claim, not a scholarly verdict, but it stuck. When older manuscripts surfaced in the nineteenth century, editors from Tischendorf to Westcott and Hort built new texts on them, and modern translations follow those instead. The Textus Receptus remains here for the reason it matters: it is what Luther, Tyndale, the Geneva translators and the King James committees actually had in front of them, so it is the text their wording has to be read against.