1 diff --git a/text/02_Git_Object_Db_Basics/0_ Git_Object_Db_Basics.markdown b/text/02_Git_Object_Db_Basics/0_ Git_Object_Db_Basics.markdown
2 index a73e0fe..013d849 100644
3 --- a/text/02_Git_Object_Db_Basics/0_ Git_Object_Db_Basics.markdown
4 +++ b/text/02_Git_Object_Db_Basics/0_ Git_Object_Db_Basics.markdown
5 @@ -1,55 +1,51 @@
6 -## The Git Object Model ##
7 +## Git 对象模型 ##
8
9 -### The SHA ###
10 +### SHA 值 ###
11
12 -All the information needed to represent the history of a
13 -project is stored in files referenced by a 40-digit "object name" that
14 -looks something like this:
15 +表示一个项目历史的所有需要的信息都被储存在文件中，这些文件以一个 40 位
16 +的"对象名称"引用，就像下面这个：
17
18 6ff87c4664981e4397625791c8ea3bbb5f2279a3
19
20 -You will see these 40-character strings all over the place in Git.
21 -In each case the name is calculated by taking the SHA1 hash of the
22 -contents of the object. The SHA1 hash is a cryptographic hash function.
23 -What that means to us is that it is virtually impossible to find two different
24 -objects with the same name. This has a number of advantages; among
25 -others:
26 -
27 -- Git can quickly determine whether two objects are identical or not,
28 - just by comparing names.
29 -- Since object names are computed the same way in every repository, the
30 - same content stored in two repositories will always be stored under
31 - the same name.
32 -- Git can detect errors when it reads an object, by checking that the
33 - object's name is still the SHA1 hash of its contents.
34 -
35 -### The Objects ###
36 -
37 -Every object consists of three things - a **type**, a **size** and **content**.
38 -The _size_ is simply the size of the contents, the contents depend on what
39 -type of object it is, and there are four different types of objects:
40 -"blob", "tree", "commit", and "tag".
41 -
42 -- A **"blob"** is used to store file data - it is generally a file.
43 -- A **"tree"** is basically like a directory - it references a bunch of
44 - other trees and/or blobs (i.e. files and sub-directories)
45 -- A **"commit"** points to a single tree, marking it as what the project
46 - looked like at a certain point in time. It contains meta-information
47 - about that point in time, such as a timestamp, the author of the changes
48 - since the last commit, a pointer to the previous commit(s), etc.
49 -- A **"tag"** is a way to mark a specific commit as special in some way. It
50 - is normally used to tag certain commits as specific releases or something
51 - along those lines.
52 -
53 -Almost all of Git is built around manipulating this simple structure of four
54 -different object types. It is sort of its own little filesystem that sits
55 -on top of your machine's filesystem.
56 -
57 -### Different from SVN ###
58 -
59 -It is important to note that this is very different from most SCM systems
60 -that you may be familiar with. Subversion, CVS, Perforce, Mercurial and the
61 -like all use _Delta Storage_ systems - they store the differences between one
62 -commit and the next. Git does not do this - it stores a snapshot of what all
63 -the files in your project look like in this tree structure each time you
64 -commit. This is a very important concept to understand when using Git.
65 +你会在 Git 的各个地方看到这些 40 个字符组成的字符串。在每一种情况下，这个名字通过
66 +计算对象内容的 SHA1 哈希值取得。 SHA1 哈希值是一个密码学哈希函数。对我们来说，
67 +这意味着事实上不可能根据同一个名字找到两个不同的对象。这具有很多优势，其中：
68 +
69 +- Git 可以很快地区分两个对象是不是相同的，只要比较名字。
70 +- 因为在每个仓库中都以相同的方式计算对象名称，因此储存在两个仓库中的相同
71 + 内容总是以相同的名字存储。
72 +- Git 可以在读取一个对象的时候侦测错误，只要检查这个对象的名字是否仍然是它
73 + 内容的 SHA1 哈希值。
74 +
75 +### 对象 ###
76 +
77 +每个对象包含三件事 ──**类型**，**大小**和**内容**。_大小_很简单，就是内容的
78 +大小；内容则取决于对象的类型。对象有四种不同的类别： "blob", "tree", "commit"
79 +和 "tag"。
80 +
81 +- 一个 **"blob"** 用来储存文件数据 ──它通常是一个文件。
82 +- 一个 **"tree"** 基本上很像一个目录 ──它索引一组其他的 tree 或者/和
83 + blob （比如：文件和子目录）。
84 +- 一个 **"commit"** 指向一个单独的 tree，作为项目在某个特定的时间点上的标记。
85 + 它包含那个时间点的元信息，比如时间戳，最后 commit 为止的改变的作者，指向之前
86 + commit 的指针，等等。
87 +- 一个 **"tag"** 是用来标记特定 commit 在某些方面特别的一种方法。它通常用来
88 + 标记指定的 commit 作为特定的发行，或者累死的东西。
89 +
90 +Git 几乎所有的建设都是围绕这种四个不同的对象类型组成的简单结构。它是一种构建
91 +在你机器的文件系统之上的自由小文件系统。
92 +
93 +### 和 SVN 的区别 ###
94 +
95 +需要重点指出的是，这和你以前所熟悉的大多数 SCM 系统都非常不同。Subversion, CVS,
96 +Perforce, Mercurial 以及所有类似使用 _Delta 存储_ 的系统储存一个 commit 和下一个
97 +commit 之间的差别。Git 不这么做 ──你每次 commit 时，它储存你项目里每次 commit
98 +的 tree 结构的所有文件的快照。这是使用 Git 时需要理解的重要观念。
99 +
100 +### 术语对照 ##
101 +
102 +- object： 对象
103 +- model： 模型
104 +- hash：哈希
105 +- repository: 仓库
106 +- project：项目
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