The software development industry suggests various approaches to user modelling based on different principles. A user model can be based on system functions, on users' goals or on users' needs, and each approach leads to different results.
Each approach has its own area of application, and the analyst should understand when modelling methods are best to be used, when different methods can or cannot be combined.
I will talk about three main methods of users' modelling and their place in the development of modern IT systems. We'll consider the situations in which these methods work best and what problems arise when the wrong method is chosen.