Who Wrote the Gospel of John?

Question:

Who wrote the Gospel of John, the Epistles of John, and Revelation?  Were they written by Apostle John, the son of Zebedee or different people named John...?
  
My Reply:
The gospel of John is believed to have been written by the apostle. The defense of this includes the fact that he often mentioned himself, but gave himself nicknames (the disciple Jesus loved, the one disciple who ran faster than Peter, etc.). Another is because it's in sync with the first letter claiming his name (1 John). It's also the same Greek style of writing.

The 2nd letter of John, though, doesn't claim to be written by John, but by an elder. I don't know why it's called John 2. I believe it's the same situation with John 3.

Revelation: Though nobody's completely positive that it was John the disciple who wrote it, it's understood that it was since he was banished on an island for some time, as is understood also in Revelation. So his history is in sync with what he reported in the book.
---Pastor Andy