除了Nick所说的，您还可以在流式线:并行软件开发的分支模式中找到更多信息

在这个图中，main是主干，rel1- maintenance是分支，1.0是标记。

嗯，我不确定我同意尼克重新标签类似于一个分支。标签只是一个标记

Trunk would be the main body of development, originating from the start of the project until the present. Branch will be a copy of code derived from a certain point in the trunk that is used for applying major changes to the code while preserving the integrity of the code in the trunk. If the major changes work according to plan, they are usually merged back into the trunk. Tag will be a point in time on the trunk or a branch that you wish to preserve. The two main reasons for preservation would be that either this is a major release of the software, whether alpha, beta, RC or RTM, or this is the most stable point of the software before major revisions on the trunk were applied.

在开源项目中，不被项目涉众接受的主要分支可以成为分叉的基础——例如，与其他源代码共享共同起源的完全独立的项目。

分支和标记子树与主干的区别如下:

Subversion allows sysadmins to create hook scripts which are triggered for execution when certain events occur; for instance, committing a change to the repository. It is very common for a typical Subversion repository implementation to treat any path containing "/tag/" to be write-protected after creation; the net result is that tags, once created, are immutable (at least to "ordinary" users). This is done via the hook scripts, which enforce the immutability by preventing further changes if tag is a parent node of the changed object.

Subversion从1.5版开始还增加了与“分支合并跟踪”相关的特性，这样提交到分支的更改就可以合并回支持增量式“智能”合并的主干中。

我不太确定“标签”是什么，但分支是一个相当常见的源代码控制概念。

基本上，分支是在不影响主干的情况下对代码进行更改的一种方式。假设您想要添加一个相当复杂的新功能。您希望能够在进行更改时检入更改，但在完成该特性之前不希望它影响trunk。

首先创建一个分支。这基本上是创建分支时的主干副本。然后在分支中完成所有工作。在分支中所做的任何更改都不会影响trunk，因此trunk仍然可用，允许其他人继续在那里工作(比如做错误修复或小的增强)。一旦你的特性完成了，你就可以把分支集成回主干中。这将把所有的更改从分支移动到主干。

人们为分支使用了许多模式。如果您有一个同时支持多个主要版本的产品，通常每个版本都是一个分支。在我工作的地方，我们有一个QA分支和一个生产分支。在向QA发布代码之前，我们将变更集成到QA分支，然后从那里进行部署。当发布到产品时，我们从QA分支集成到生产分支，所以我们知道在生产中运行的代码与QA测试的代码是相同的。

这里是维基百科上关于分支的条目，因为它们可能比我能更好地解释事情。：）

当我在OpenCV 2计算机视觉应用编程烹饪书的作者的网站上查找时，我发现了这个关于SVN的很棒的教程，我想我应该分享一下。

他有一个关于如何使用SVN的教程，以及短语“trunk”、“tag”和“branch”的含义。

直接引用自他的教程:

The current version of your software project, on which your team is currently working is usually located under a directory called trunk. As the project evolves, the developer updates that version fix bugs, add new features) and submit his changes under that directory. At any given point in time, you may want to freeze a version and capture a snapshot of the software as it is at this stage of the development. This generally corresponds to the official versions of your software, for example, the ones you will deliver to your clients. These snapshots are located under the tags directory of your project. Finally, it is often useful to create, at some point, a new line of development for your software. This happens, for example, when you wish to test an alternative implementation in which you have to modify your software but you do not want to submit these changes to the main project until you decide if you adopt the new solution. The main team can then continue to work on the project while other developer work on the prototype. You would put these new lines of development of the project under a directory called branches.

它们没有任何正式的含义。文件夹就是文件夹 SVN。它们是组织项目的一种普遍接受的方式。

The trunk is where you keep your main line of developmemt. The branch folder is where you might create, well, branches, which are hard to explain in a short post. A branch is a copy of a subset of your project that you work on separately from the trunk. Maybe it's for experiments that might not go anywhere, or maybe it's for the next release, which you will later merge back into the trunk when it becomes stable. And the tags folder is for creating tagged copies of your repository, usually at release checkpoints.

但正如我所说，对于SVN，文件夹就是文件夹。分支、主干和标签只是一种约定。

我随意使用“复制”这个词。SVN实际上并不完全复制存储库中的内容。

我认为一些混淆来自标记概念和SVN中的实现之间的差异。对于SVN来说，标签是一个分支，它是一个副本。修改标签被认为是错误的，事实上，像TortoiseSVN这样的工具会警告你，如果你试图用../tags/..在路上。