**1. Introduction**

In the field of simulation and gaming, the problem of software usability has been raised for many years [1–4], perhaps even since the practice of gaming simulation took off in the 1960s [5]. Simulation and gaming is an interdisciplinary domain which rallies, among others, the disciplines of education and modelling, and which aim at helping people to acquire knowledge and skills on complex subjects in which social dynamics are intertwined with technical and/or environmental problems [6–8]. Gaming is the process by which learning takes place. Simulation, on the other hand, is the process used to represent the many interactions, including social interactions, that make up the complex subject being addressed. The range of uses varies widely: city planning, risk management, natural resources management, land use planning and business management are just a few examples. Gaming simulations, understood as tools or artefacts, are used both in teaching and for decision support [9]. In order to illustrate what a gaming simulation can look like, we briefly describe an example of application. LittoSIM is a gaming simulation application used with technicians and decision-makers in coastal cities to help them develop new strategies for coastal flooding risk management [10]. The simulation artefact can be used to simulate coastal flooding that occurs during storms, the extent and intensity of which depends on the coastal defences and the land use development

strategies decided by the players. Players take part in gaming sessions during which they select which coastal defence measures to use (based on various economic, regulatory and operational constraints) and adapt how the land in their fictitious urban areas is used from one year to the next, in an attempt to manage this major risk. Experiential learning is achieved both through the various strategies that the players test using the simulation system and through discussions and exchanges of views between the players on the decisions they need to make [11]. This example illustrates how simulation and the gaming process intertwine to create experiences for participants that help them to acquire new knowledge, reflect on a particular situation and develop new skills for dealing with that type of situation.

Between the end of the 1950s and the end of the 1960s, the use of simulation and gaming on the one hand and computer simulation on the other developed concurrently as two ways of approaching decision support in complex situations [12]. Computer simulation focuses on processing data, finding optimal solutions and comparing various typical scenarios. Simulation and gaming focuses on the lived experience (and in particular the emotional and sensitive dimensions of the lived experience) and on the use of communication and collective intelligence to solve a problem based on each other's opinions and find compromises between everyone's interests [13, 14]. The question that arises for designers of these tools, who are aiming to use simulation as a way of facilitating experiential learning, is **whether the use of computer simulation within a gaming simulation artefact slows down, or even restricts, the learning potential for the users**. Although computer technology and simulation methods have evolved, this question remains topical for simulation and gaming practitioners, who in practice articulate this dilemma as a choice that needs to be made at the start of the development phase for a new application between developing a computer game or developing an haptic game (haptic in the sense that it does not involve any human-computer interactions).

The first section presents the issue of computerization in the domain of simulation and gaming and the different types of configuration of computerised gaming simulations. The second section explores the effects of computerisation, both from the users' perspective and from the developers' perspective. The last section presents some recommendations and advances in research to go beyond the limits of usability of computerised applications.
