Introduction to the JSS special issue of Web 2.0 engineering: New practices and emerging Challenges
The number and complexity of Web applications and the mount of information they offer has been continuously growing in he context of the Web 2.0. Importantly, Web 2.0 applications need eb engineering design methods to provide mechanisms to accelrate and improve their development and maintenance. To this im methods or tools based on recent techniques of model-driven ngineering discipline [e.g., MDA (OMG, 2003), ADM (Newcomb, 005), Architecture-Centric MDA, Aspect-Oriented Development, tc.) should be provided for developing such applications (such s social computing, Rich Internet Applications, Service-Oriented rchitecture, etc.). Moreover, some new issues need to be addressed, due to the ncreased level of sophistication of the modern Web applications, ommonly referred to as Web 2.0 applications. These applicaions foster the user involvement in the production of contents, nnotations, and evaluations. Therefore, one of the main issues f the Web 2.0 is the high level of interaction of the user with he Web application. For this reason, the development of Web .0 applications should be focused on the user, thus requirements ngineering techniques should be considered in this context. In ddition, requirements engineering is a complex activity which uccess depends on the stakeholders’ participation. Thus, the techiques proposed in the requirements engineering field need a ore participative environment to support effective collaboration mong stakeholders for developing Web 2.0 applications. Also, as a result of the user interaction, a huge amount of userenerated content is populating the Web. The need to manage hem in an efficient manner lies behind a set of new topics that re gaining momentum in the Web scenario. Among them, the election of trustworthy contents from the Web, such as content redibility and author reputation outstands. Another increasingly mportant topic in this new environment is the development of ashups through the integration of contents and functions that are rovided by third parties that open their APIs toward developers nd end users. Regarding this new generation of applications while everal efforts have been so far devoted to the production of authorng environments and development tools, and to the definition of orresponding enabling technologies, there is a lack of proposals or the definition of key quality principles and evaluation methods or the component development, selection, and integration. The goal of this special issue is to provide an overview of research n the field of Web 2.0 engineering. The call for papers was very sucessful and attracted 23 submissions. All submitted papers went