Apple Macintosh System 7.5 - Manual (Page 7)

If you have already installed System 7
This handbook describes the upgrade to System 7.5 for the Macintosh. If all
users in your group have already installed System 7.0 or a later version, you
may be able to skip some of the tasks described later in this book.
Application software
Most application programs that were compatible with system software version
7.0 or 7.1 should be compatible with System 7.5. If you need information about
a program’s compatibility with System 7.5, contact the manufacturer of that
program.
Network software
New versions of some network software are installed with System 7.5. For
specific information about AppleTalk, AppleShare, and other network
services, see “Quick Reference: Products That May Need Upgrading” and
“Group Upgrade Q&A” in Chapter 3.
LaserWriter drivers
New versions of LaserWriter drivers are installed with System 7.5, but these
are required only on computers being upgraded. The new drivers can coexist
on your network with version 7.0 or 7.1 drivers.
3 Before You Begin