看看Scott Chacon不久前的帖子。

我认为git以“更复杂”而闻名，尽管在我的经验中，它并没有比它需要的更复杂。在我看来，git模型更容易理解(标签包含提交(以及指向零个或多个父提交的指针)包含树，包含blob和其他树…完成)。

git并不比mercurial更令人困惑，这不仅仅是我的经验。我建议你再读一遍Scott Chacon关于这个问题的博文。

After reading all over that Mercurial is easier (which I still believe it is, after all the internet community is of the opinion), when I started working with Git and Mercurial I felt Git is relatively simpler for me to adapt to (I started off with Mercurial with TortoiseHg) when working from the command line, mainly because the git commands were named appropriately according to me and are fewer in number. Mercurial has different naming for each command that does a distinct job, while Git commands can be multipurpose according to situation (for eg, checkout). While Git was harder back then, now the difference is hardly substantial. YMMV.. With a good GUI client like TortoiseHg, true it was much easier to work with Mercurial and I did not have to remember the slightly confusing commands. I'm not going into detail how every command for the same action varied, but here are two comprehensive lists: 1 from Mercurial's own site and 2nd from wikivs.

╔═════════════════════════════╦════════════════════════════════════════════════════════════════════════════════════════════════╗
║           Git               ║                Mercurial                                                                       ║
╠═════════════════════════════╬════════════════════════════════════════════════════════════════════════════════════════════════╣
║ git pull                    ║ hg pull -u                                                                                     ║
║ git fetch                   ║ hg pull                                                                                        ║
║ git reset --hard            ║ hg up -C                                                                                       ║
║ git revert <commit>         ║ hg backout <cset>                                                                              ║
║ git add <new_file>          ║ hg add <new_file> (Only equivalent when <new_file> is not tracked.)                            ║
║ git add <file>              ║ Not necessary in Mercurial.                                                                    ║
║ git add -i                  ║ hg record                                                                                      ║
║ git commit -a               ║ hg commit                                                                                      ║
║ git commit --amend          ║ hg commit --amend                                                                              ║
║ git blame                   ║ hg blame or hg annotate                                                                        ║
║ git blame -C                ║ (closest equivalent): hg grep --all                                                            ║
║ git bisect                  ║ hg bisect                                                                                      ║
║ git rebase --interactive    ║ hg histedit <base cset> (Requires the HisteditExtension.)                                      ║
║ git stash                   ║ hg shelve (Requires the ShelveExtension or the AtticExtension.)                                ║
║ git merge                   ║ hg merge                                                                                       ║
║ git cherry-pick <commit>    ║ hg graft <cset>                                                                                ║
║ git rebase <upstream>       ║ hg rebase -d <cset> (Requires the RebaseExtension.)                                            ║
║ git format-patch <commits>  ║ hg email -r <csets> (Requires the PatchbombExtension.)                                         ║
║   and git send-mail         ║                                                                                                ║
║ git am <mbox>               ║ hg mimport -m <mbox> (Requires the MboxExtension and the MqExtension. Imports patches to mq.)  ║
║ git checkout HEAD           ║ hg update                                                                                      ║
║ git log -n                  ║ hg log --limit n                                                                               ║
║ git push                    ║ hg push                                                                                        ║
╚═════════════════════════════╩════════════════════════════════════════════════════════════════════════════════════════════════╝

Git在内部保存提交文件的每个版本的记录，而Hg只保存更改集，占用空间更小。与Hg相比，Git更容易改变历史，但它又是一个令人讨厌或喜欢的特性。前者我喜欢Hg，后者我喜欢Git。

我在Hg中错过的是Git的子模块特性。Hg有subrepos，但那不是Git的子模块。

围绕这两者的生态系统也会影响一个人的选择:Git必须更受欢迎(但这无关紧要)，Git有GitHub，而Mercurial有BitBucket, Mercurial有TortoiseHg，我还没有看到与Git一样好的同类产品。

每一种都有它的优点和缺点，用它们中的任何一种你都不会输。

在我目前的工作中，我已经使用Git一年多一点，在此之前，我在上一份工作中使用Mercurial一年多一点。我将从用户的角度提供一个评估。

首先，两者都是分布式版本控制系统。分布式版本控制系统需要改变传统版本控制系统的思维方式，但一旦理解了它们，实际上在许多方面工作得更好。出于这个原因，我认为Git和Mercurial都比Subversion、Perforce等要优越得多。分布式版本控制系统与传统版本控制系统之间的差异远远大于Git与Mercurial之间的差异。

然而，Git和Mercurial之间也存在显著的差异，这使得它们都更适合于自己的用例子集。

Mercurial比较容易学习。在使用Mercurial几周后，我几乎不需要参考文档或笔记;即使在使用Git一年之后，我仍然需要定期查阅我的笔记。Git要复杂得多。

This is partly because Mercurial is just plain cleaner. You rarely have to branch manually in Mercurial; Mercurial will create an anonymous branch automatically for you if and when you need it. Mercurial nomenclature is more intuitive; you don't have to worry about the difference between "fetch" and "pull" as you do with Git. Mercurial is a bit less buggy. There are file name case sensitivity issues that used to cause problems when pushing projects across platforms with both Git and Mercurial; this were fixed in Mercurial some time ago while they hadn't been fixed in Git last I checked. You can tell Mercurial about file renames; with Git, if it doesn't detect the rename automatically - a very hit or miss proposition in my experience - the rename can't be tracked at all.

The other reason for Git's additional complication, however, is that much of it is needed to support additional features and power. Yes, it's more complicated to handle branching in Git - but on the other hand, once you have the branches, it's not too difficult to do things with those branches that are virtually impossible in Mercurial. Rebasing branches is one of these things: you can move your branch so that its base, instead of being the state of the trunk when you branched, is the state of the trunk now; this greatly simplifies version history when there are many people working on the same code base, since each of the pushes to trunk can be made to appear sequential, rather than intertwined. Similarly, it's much easier to collapse multiple commits on your branch into a single commit, which can again help in keeping the version control history clean: ideally, all the work on a feature can appear as a single commit in trunk, replacing all the minor commits and subbranches that the developer may have made while developing the feature.

Ultimately I think the choice between Mercurial and Git should depend on how large your version control projects are, measured in terms of the number of people working on them simultaneously. If you have a group of a dozen or more working on a single monolithic web application, for example, Git's more powerful branch management tools will make it a much better fit for your project. On the other hand, if your team is developing a heterogeneous distributed system, with only one or two developers working on any one component at any one time, using a Mercurial repository for each of the component projects will allow development to proceed more smoothly with less repository management overhead.

底线:如果你有一个庞大的团队在开发一个庞大的应用程序，那就使用Git;如果您的单个应用程序很小，任何规模都来自于这些应用程序的数量而不是大小，请使用Mercurial。

我想你们可以通过这两个视频了解这些系统的相似或不同之处:

Linus Torvalds谈Git (http://www.youtube.com/watch?v=4XpnKHJAok8) 布莱恩·奥沙利文谈Mercurial (http://www.youtube.com/watch?v=JExtkqzEoHY)

它们在设计上非常相似，但在实现上却非常不同。

我使用Mercurial。就我对Git的理解而言，Git的一个主要不同之处在于它跟踪文件的内容而不是文件本身。Linus说，如果你将一个函数从一个文件移动到另一个文件，Git会告诉你整个移动过程中该函数的历史。

他们还说git在HTTP上更慢，但它有自己的网络协议和服务器。

Git作为SVN的厚客户端比Mercurial更好。可以对SVN服务器进行拉推操作。这个功能在Mercurial中仍处于开发阶段

Mercurial和Git都有非常好的网络托管解决方案(BitBucket和GitHub)，但谷歌代码只支持Mercurial。顺便说一下，他们对Mercurial和Git进行了非常详细的比较，以决定支持哪一个(http://code.google.com/p/support/wiki/DVCSAnalysis)。它有很多好的信息。

Mercurial几乎完全是用python编写的。Git的核心是用C语言编写的(应该比Mercurial的更快)，工具是用sh、perl、tcl编写的，并使用标准的GNU utils。因此，它需要将所有这些util和解释器带到不包含它们的系统中(例如Windows)。

两者都支持SVN，尽管AFAIK SVN在Windows上对git的支持是坏的(可能是我不走运/蹩脚，谁知道呢)。还有一些扩展允许git和Mercurial之间的互操作。

Mercurial有很好的Visual Studio集成。上次我检查的时候，Git的插件正在工作，但是非常慢。

它们的基本命令集非常相似(init, clone, add, status, commit, push, pull等)。所以，基本的工作流程是一样的。另外，两者都有类似tortoisesvn的客户端。

Mercurial的扩展可以用python编写(这并不奇怪!)，而git的扩展可以用任何可执行形式编写(可执行二进制文件、shell脚本等)。有些扩展功能非常强大，比如git bisect。

I use both quite regularly. The major functional difference is in the way Git and Mercurial name branches within repositories. With Mercurial, branch names are cloned and pulled along with their changesets. When you add changes to a new branch in Mercurial and push to another repository, the branch name is pushed at the same time. So, branch names are more-or-less global in Mercurial, and you have to use the Bookmark extension to have local-only lightweight names (if you want them; Mercurial, by default, uses anonymous lightweight codelines, which in its terminology are called "heads"). In Git, branch names and their injective mapping to remote branches are stored locally and you must manage them explicitly, which means knowing how to do that. This is pretty much where Git gets its reputation for being harder to learn and use than Mercurial.

正如其他人在这里注意到的，有很多很多微小的差异。分支是一个很大的微分器。