Recent technological advancements have enabled the development of new communication devices and new ways to use them. Among them, touch technology is experiencing a major expansion. Indeed, its use is easy, intuitive and natural and is an excellent interface between human and machine. In this context, many studies have examined the development of touch screens whether for phones or tablets. The objective was to analyze how the user interacts with the screen to make it more ergonomic and easier to use. The results show that size, colours or locations of the interactive elements could influence the performance of the user. Although this approach is essential for the development of tactile devices, user motion analysis is equally: the upper limb is classically described as a multi-joint system with redundancy, which leads to the same movement on the screen with an infinite number of joint combinations. Very few studies have examined these biomechanical characteristics. However, such information may be relevant in the development of devices suitable for motor capabilities of users. The objective of this work was to analyze the joint organization of the upper limb during the interaction with a touch pad. Eleven healthy right handed subjects voluntarily participated to the experience. The task consisted in achieving five times a 16 pieces puzzle presented on a 10-inch touch pad. The pieces were randomly displayed at the bottom of the screen and a translucent guide was presented in the upper part. To perform the motion analysis, the trajectories of eighteen light reflective markers placed on the trunk and the right upper-limb were recorded using an optoelectronic system. Then, relative upper limb joint angles were computed according to the ISB instructions. A Hierarchy Ascending Classification was applied on the range of motion of the 15 degrees of freedom. Three groups of subjects emerged. The first one included six subjects that had an important solicitation of the proximal joints (shoulder and elbow) and a very low implication of the wrist. This organization was called “proximal strategy”. On the contrary, the second group (with five subjects) was characterized by an important mobilization of the wrist and a relative low involvement of the proximal joints. This organization was called “wrist strategy”. One subject had an important and equal solicitation of all de degrees of freedom characterizing a “neutral strategy”. From a biomechanical point of view, results revealed that there were different ways to interact with the touch pad and perform the task. This information would be relevant in the framework of ergonomics to adapt interfaces in relation to these different motor organizations. This is particularly relevant for patients with motor impairments. Indeed, the loss of a degree of freedom or control of a muscle due to trauma could significantly alter the motor organization and thus make interaction difficult or even impossible. However, future studies are needed to determine to what extent these organizations are stable drive and what are the parameters that can lead a subject to modify the organization of his gesture.