说明：  UML统一建模语言手册。本文讲述了UML的基本概念，为UML的深入理解提供了一个起点。本文共有十四个章节。
(UML Unified Modeling Language Guide. This article describes the basic concepts of UML, in order to in-depth understanding of UML provides a starting point. In this paper, a total of 14 chapters.)