Mini vMac is a miniature Macintosh emulator.
Mini vMac emulates a Macintosh Plus, one of the earliest of Macintosh computers, sold between 1986 and 1990. It can run old Macintosh software that otherwise couldn’t be used on recent computers, and so helps to preserve history, from the era when the modern user interface for computers was being defined.
Mini vMac is a spin off of the program vMac. It was originally intended to be of limited interest, a simpler version to serve as a programmers introduction to vMac. But vMac hasn’t been updated in some years, and doesn’t have a number of fixes included in Mini vMac, so Mini vMac may now be more generally useful.
To meet the goal of preserving early Macintosh software forever, Mini vMac is intended to be as simple and maintainable as possible, while still being usable enough that the software running within it is as usable as ever. Also as part of this goal, Mini vMac is intended to be easily portable to new operating systems. So far it works on Macintosh OS, Microsoft Windows, and the X Window System.
Mini vMac requires a ROM image file to run, and so can be legally used only by those who own a Macintosh Plus. This leads to the question, if you need to own the real computer to use it, what is the use of the emulator? First, a real Macintosh Plus won’t last forever. It is common for the power supply to fail. It is still legal to use the emulation after the real computer breaks. And second, the emulation is more convenient than the real thing. It is much faster (on modern computers) and you can use a better screen, keyboard, and mouse. And it is easier to transfer files between the modern computer and the emulator.
Some of the very earliest systems versions and applications won’t work on a Macintosh Plus, so Mini vMac can be recompiled to emulate the original Macintosh 128K. Mini vMac can also be recompiled to emulate the Macintosh 512K, 512Ke, and SE.
If you would like to run more modern applications that won’t work on a Macintosh Plus (which has an MC68000 processor, 4M of RAM maximum, and a 512 by 342 black and white screen), then you should look for a different emulator. Or buy a Mac.