This is the beginning of a glossary. I don't have the technical skill or background to provide decent definitions so if you see this and have the confidence to put one in then please do!

Grant Hutchinson's Glossary: http://www.splorp.com/newton/glossary/

The Glossary on UNNA: http://tools.unna.org/glossary/

Index:
 ATA
Bookmaker
Extensions
Inbox
Jaggies
Linear memory card
NBU
NCU
Newton Press
NTK - Newton ToolKit?
Packages
Put away
SER-001
Soups

Definitions

ATA: A file system for storage media that requires Paul Guyot's software to work.

Bookmaker: definition required

Extensions: definition required

Inbox: A catch-all storage area where emails and packages reside until they are ""put away"".

Jaggies: A condition in which the Newton loses its ability to accurately respond to input from the stylus. If you have Jaggies, drawing a straight line from one corner to the other will not produce a straight line on screen.

Linear memory card: The filing system storage media cards that are compatible with the Apple Newton.

NBU: A piece of software available for Classic Mac and Windows that provides backup facilities.

NCU: Newton Connection Utilities. This software is used to connect the Newton to the serial port of a computer so packages (below) can be loaded. It also includes utilities to back up your Newton as well as export documents.

Newton Press: definition required

Newton Took Kit (NTK): definition required

Packages: definition required

Put Away: definition required

SER-001: A serial interface card for the MP2000/MP2100 designed and built by PCBMan that provides a normal Apple serial connector so that a Newton serial dongle is not required for exchanging data. Both the existing port and the SER-001 port are active simultaneously but only one or the other should be used when making a connection. Unlike the built-in connector, the SER-001 cannot be used to wake the Newton or route audio signals. Installation of the SER-001 requires opening the case of the MessagePad but does not require soldering.

Soups: definition required