功能简单的块文本列表控件，主要功能为将列表项扩展为可显示多行文字，并且可为每个列表项设置不同的文字显示！-Features a simple text list of control blocks, the main function for a list of items can be extended to display multiple lines of text, and can be set for each list item display different text!

This chapter works with the next six chapters to act as a foundation for the technology discussions that follow. In this chapter, some fundamental concepts and terms used in the evolving language of internetworking are addressed. In the same way