Zoom is a Z-Machine, which means that it plays text adventure games written in ZCode. The original games were written by a company called 'Infocom' in the 80's: these are available on the Infocom Masterpieces CD, published by Activision.

Unfortunately, Activision seems to have lost interest in this title - however, there are a few companies that have a stock of this CD.

In around 1993, a compiler called 'Inform' was released that allowed ordinary mortals to create their own ZCode adventures. This sparked quite a revival, and there are many games available for download here (ftp://ftp.ifarchive.org/if-archive/games/infocom/)
Inform itself has a homepage here (http://www.gnelson.demon.co.uk/inform.html)

The Mac OS X version supports all the features of the X-Windows version, has a much better user interface, and supports several extra features, such as speech output.

Here are some key features of "Zoom":

· Full support for the Z-Machine as defined by the Z-Machine specification version 1.0/1.1 draft 6.
· Timed input.
· Multiple fonts.
· Font 3.
· Mouse.
· Support for version 6, including pictures and the mouse.
· Text input history.
· Scrollback.
· Dynamic window resizing and font changing.
· Zoom also provides support for speech output.
· Quickdraw or Quartz rendering (the Quartz rendering is somewhat experimental, but looks a lot better than Quickdraw...)
· The finder can be used to launch both games and saved game files.