A package manager does as what it says - it manages software packages that make up your installation.

setup.exe is the installation program for any software package, including Win 9x.

It has two meanings

1)A special method of distributing and installing software (or software upgrates) to a computer. For example, on a Macintosh computer, a package usually means "software." It's specifically a directory , presented as a single file, that contains all the information the Mac OS X Installer application needs to install your software. That includes the software itself, as well as files that are used only during the installation process. In a Windows environment it is sometimes called an installation package or update package.

2) Multiple software programs that work together (or performs similar functions) and is bundled and sold together as a software package.

there is a piece of software called "Installshield" installshield. it is probably the most popular software installation package around

One can purchase an EventID software package via the official Event ID website. One can also obtain support via the EventID website once the installation is complete.