O2 is the UK's leading provider of mobile phones and broadband, offering the best mobile phone, sim only, and broadband deals. Save money by buying direct!

中国计费网是中国第一个定位于计费和OSS领域的专业媒体，致力于推动中国电信行业的发展，是业内唯一定位于及时、全面报道国内外计费&OSS领域相关信息的中文网站，是业内人士获取行业信息的重要专业资讯网站。

Red Hat is the world's leading open source technology solutions provider with offerings including Red Hat Enterprise Linux, open source applications, security and systems management, virtualization, Services Oriented Architecture (SOA) solutions.

Software tools and techniques for global software development. Dr. Dobb's features articles, source code, blogs,forums,video tutorials, and audio podcasts, as well as articles from Dr.

定位于中国企业软件高端专业网站，以Java技术为平台载体，在中国引导、研究和学习全球最先进的企业软件思想；提供与全球软件架构同步的、中立的技术咨询和培训服务。

SourceForge.net. Fast, secure and free downloads from the largest Open Source applications and software directory.

中文JAVA技术网 推广和普及Java技术，为国内众多的Java爱好者提供一个“平等自由协作创造”的开放式交流环境，提供Java专题文章、Java论坛、资源下载、博客和开源项目等栏目。

Whether you're creating software for mobile devices, desktops, enterprise systems, the Internet, or games, java.sun.com gets you what you need: code samples, developer tools, downloads, open-source projects, resource centers, and support.

Codeguru is where developers can come to share ideas, articles, questions, answers, tips, tricks, comments, downloads, and so much more related to programming in areas including C++, Visual C++, C#, Visual Basic, ASP, ASP.NET, Java, and more.

开发者在线面向软件开发领域人群。核心内容覆盖软件开发技术的各个层面：C/S开发、数据库开发、SOA中间件、WEB开发、移动嵌入式、项目管理、网页设计。