In word processing systems, a feature that enables blocks of recorded text to be indented with different margins, while still retaining the original(fixed) margin settings.
字（词）处理技术中的一种功能特性，它使记录的正文块按不同边线缩排，同时仍然保持原来（固定的）边线设置。
An indented or concave surface or area.
凹陷，洼地凹的表面或地区
The blank space between a margin and the beginning of an indented line.
行首空格白边与缩进行行首之间的空白处
