History of aGPSS

GPSS originated within IBM already in the 1960s and has since then, seen over the years, been the most widely used package for discrete-event simulation, implying that there are a great amount of GPSS programs and text books available.

aGPSS is a streamlined version of IBM GPSS. aGPSS is the result of an educational development process, based on feedback from many of the over 10,000 students that we have taught GPSS. We started teaching IBM GPSS in the late seventies at the Stockholm School of Economics. Since our students experienced several problems with this GPSS version, we started to develop our own GPSS version. Our efforts were focused on creating a GPSS version that would be very easy to learn and use, and with several novice teachers, also easy to teach.

Initially, our GPSS was text based, just like the other GPSS versions. In the late eighties we got funds from the Swedish KK-foundation to develop a Web based GPSS, as part of their efforts of supporting new Web-based teach-ware. The new software, called WebGPSS, was not only web-based, developed in Java, but an easy-to-use GUI was also added. This development was a co-operative effort involving, among others, the KK-foundation, the Stockholm School of Economics and Blekinge Technical University. The first version of WebGPSS was released in 1999. It was at first only available as an Applet on the Web.

Due to problems with accessing the server from other countries and server overloading, when many students ran aGPSS simultaneously, there was a demand for a stand-alone version for Windows on a CD. This version eventually replaced the Web version and it was then found suitable to change the name to aGPSS, stressing it is meant to be the first simulation system for beginners.

The development efforts continue. The most recent additions are an easy-to-use interface to Proof animation, allowing also for automatic animation with dynamic block statistics, and an aGPSS version for the Macintosh.