The documents in the TechSupportNotes directory were created by NeXT Technical Support to cover certain topics that aren't treated fully in the main NeXT Technical Documentation.  They are more in-depth than NextAnswers, but most of them have been shipped as part of NextAnswers in the past.  Starting with October 1990, these have been separated out to reduce the size of the tar files.

We recommend installing them in /LocalLibrary/TechSupportNotes/, or possibly /LocalLibrary/NextAnswers/TechSupportNotes/.  See the instructions in the file INSTALL.wn that is shipped with NextAnswers (and with the NA_Supplements) for details on which files from NextAnswers should be moved to TechSupportNotes.

The name of the files in TechSupportNotes on the archive server include a date indicating the last time the document was updated.  For example, the file SerialPortDoc.wn_April_90.tar.Z hasn't been updated since April, so if you've obtained NextAnswers in the past you probably already have it.

The files as of January 1991 are:

2.0EntryPoint.rtf 
ExceptHandling.wn_July_90.tar.Z
SerialPortDoc.wn_April_90.tar.Z
NeXT_Style_Guide.wn_July_90.tar.Z
Sybase.wn_May_90.tar.Z
PerformanceTuning.wn_April_90.tar.Z
UUCP.wn_Oct_90.tar.Z

The first five of these were formerly the following NextAnswers, respectively:

appkit.541.wn
sysadmin.440.wn
misc.542.wn
sybase.364.wn
performance.455.wn

2.0EntryPoint.rtf is the only new Technical Support Note since the November TechSupportNotes release.