from this thread (I have added some additional notes and emphasis)
1. Over 5,700 manuscripts of the Greek NT existing are referred to as Byzantine. Given the quantity, they are also referred to as the "majority".
2. Sometime in the 19th century two Egyptian manuscripts were found:
2.1 Sinaiticus - also called Aleph, named after the monastery location of the discovery
2.2 Vaticanus, also called B, and both these documents are commonly assumed to be dated around the 4th century.
2.3 These manuscripts are also referred to as the Alexandrian manuscripts. Hence, in these sort of discussions we often find there are two basic camps, Byzantine and Alexandrian.
3. Erasmus, in 1516, published a version of the NT using six of the Byzantine texts available to him at the time. From this comes the "Majority Text" translation label. (my note - actually, I believe this is considered as the Textus Receptus or Received Text of which 6 of the Majority texts were the source)
4. The Geneva Bible, Luther's translation into German, and the KJV translation trace back to the Erasmus translation.
5. Scholars from the Alexandrian position hold that the two Alexandrian manuscripts (Aleph and B) are the oldest and most reliable versions of the NT.
6. These scholars have published a Critical Text (CT) that drew heavily upon the Alexandrian manuscripts (Aleph and B). (my note - but is also substantiated by the discovery of and inclusion of even older manuscripts, as well as Byzantine or Majority texts.)
Like I said - excellent summary!