苹果电脑公司（Apple Computer, Inc.）为用户提供了全套免费的Cocoa程序开发工具，这套工具

就是我们所说的Xcode。它随着Mac OS X一起发行，当然，你也可以在苹果公司的网站下载。-Apple Computer (Apple Computer, Inc.) To provide users with a full set of free tools for Cocoa developers, this tool is what we call Xcode. It, together with the Mac OS X issue, of course, you can download Apple' s Web site.