The technical report describes the Multi-Maps SOM prototype and its visualization-based analysis functions.Multi-Maps SOM prototype is based on Kohonen self-organizing map (SOM) for clustering and mapping according to a multi-maps extension. The prototype is called Multi-SOM in this report.The principles of Multi-SOM are exposed in the most formal possible way in chapter 1. The following bases are detailed: the notion of viewpoint is introduced, the map division into logical areas, the way of labelling the clusters, the inter-maps communication mechanism and the map generalization mechanism.The characteristic of Multi-Maps SOM prototype is the dynamic visual-based information analysis provides to user. The user can visualize the relation between maps by using an inter-map communication mechanism, browse each map and get information about the cluster and access to the associated documents. All these functionalities are presented in the chapter 2.Chapter 3 covers the crucial problem of data preparation in the Multi-SOM environment. This is an important factor determining the success of a practical application as this chapter shows with a real example on Web data (collected in WP3 as deliverable D-3.1 by CSIC)In chapter 4, we justify the technological choices and expose all information relating to the design of the prototype. Such as, the choice of the programming language, techniques of programming, the implemented model, the implemented algorithm, input/output flows and events connection between components of the application.