574 Copyright © 2010, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 50 The Usability of Social Software Lorna Uden Staffordshire University, UK Alan Eardley Staffordshire University, UK INTRODUCTION AND BACKGROUND Social software has emerged as a driving force of Web 2.0. The term Web 2.0 was coined by Tim O’Reilly (2005) to describe a sea change in web services and technologies. It should be noted that Web 2.0 is not a single development but rather a heterogeneous mix of new and emergent technolo- gies. Overall, there is an increasing presence of social software applications that allow users to communi- cate, collaborate, and share their personal interests. This chapter introduces a usability perspective on social software and offers guidance for evaluating the usability of social software applications. Bryant (2007) defines social software as a com- bination of various social tools within a growing ecosystem of online data and services, all joined together (aggregated) using common protocols, micro-formats and Application Programming In- terface (API) methods. It is also underpinned by some general principles about engaging people as active participants in online social networks and communities to achieve new and exciting effects through distributed collaboration, co-production and ABSTRACT Emergent Web 2.0 technologies and applications (such as blogs, wikis, podcasts, mashups, and folk- sonomies) present a range of opportunities and benefts and are increasingly used by people to interact with each other. Despite the growing popularity of social software, there is a lack of research on the usability of these tools. This chapter focuses on how users interact with Web 2.0 technology, discusses a conceptual framework for a usability evaluation of social software, describes the different types of social software applications, and offers guidelines for their usability evaluation. The argument advanced is that social software usability should be viewed as a set of principles and practices aimed to deliver more service-orientated Web 2.0-based applications. DOI: 10.4018/978-1-60566-368-5.ch050