I may have found one further difference of a minor nature. I have my python environments under /usr rather than /home or whatever. In order to install to it, I would have to use sudo install pip. For me, the undesired side effect of sudo install pip was slightly different than what are widely reported elsewhere: after doing so, I had to run python with sudo in order to import any of the sudo-installed packages. I gave up on that and eventually found I could use sudo conda to install packages to an environment under /usr which then imported normally without needing sudo permission for python. I even used sudo conda to fix a broken pip rather than using sudo pip uninstall pip or sudo pip --upgrade install pip.

引用Conda for Data Science在Continuum网站上的文章:

Conda vs pip Python programmers are probably familiar with pip to download packages from PyPI and manage their requirements. Although, both conda and pip are package managers, they are very different: Pip is specific for Python packages and conda is language-agnostic, which means we can use conda to manage packages from any language Pip compiles from source and conda installs binaries, removing the burden of compilation Conda creates language-agnostic environments natively whereas pip relies on virtualenv to manage only Python environments Though it is recommended to always use conda packages, conda also includes pip, so you don’t have to choose between the two. For example, to install a python package that does not have a conda package, but is available through pip, just run, for example:

conda install pip
pip install gensim

要回答最初的问题， 对于安装包，PIP和Conda是完成相同任务的不同方式。两者都是安装包的标准应用程序。主要的区别是包文件的来源。

PIP/PyPI将有更多的“实验性”包，或者更新的、不太常见的包版本 Conda通常会有更完善的包或版本

一个重要的警告提示:如果使用两个源(pip和conda)在同一环境中安装包，以后可能会导致问题。

重建环境将更加困难 修复包不兼容性变得更加复杂

最佳实践是选择一个应用程序(PIP或Conda)来安装包，并使用该应用程序安装所需的任何包。 然而，仍然有许多例外或理由在conda环境中使用pip，反之亦然。 例如:

如果您需要的包只存在于一个包上，则 其他人没有。 您需要一个只在一个环境中可用的特定版本

pip仅用于Python

conda只适用于Anaconda +其他科学包，如R依赖等。并不是每个人都需要蟒蛇，因为它已经和Python一起出现了。Anaconda主要是为那些做机器学习/深度学习等的人准备的。普通的Python开发人员不会在他的笔记本电脑上运行Anaconda。

WINDOWS用户

“标准”包装工具的情况最近有所改善:

截至2015年9月11日，pypi本身的车轮包装数量为48%(2015年5月为38%，2014年9月为24%)， 最新的python 2.7.9版本现在支持开箱即用的wheel格式，

“标准”+“微调”包装工具的情况也在改善:

你可以在http://www.lfd.uci.edu/~gohlke/pythonlibs上找到几乎所有的科学软件包， mingwpy项目可能有一天会给Windows用户带来一个“编译”包，允许他们在需要的时候从源代码安装所有东西。

“Conda”包装对于它所服务的市场来说仍然更好，并强调了“标准”应该改进的地方。

(此外，在标准wheel系统和conda系统或buildout中的依赖规范multiple-effort不是很python化，如果所有这些打包“核心”技术可以通过某种PEP聚合在一起就好了)

引用Conda: Myths and misconcepts(一个全面的描述):

...

误解3:Conda和pip是直接竞争对手

事实:Conda和pip服务于不同的目的，并且只在一小部分任务上直接竞争:即在孤立的环境中安装Python包。

Pip是Pip安装包的缩写，是Python官方认可的包管理器，最常用于安装发布在Python包索引(PyPI)上的包。pip和PyPI都由Python打包管理局(PyPA)管理和支持。

In short, pip is a general-purpose manager for Python packages; conda is a language-agnostic cross-platform environment manager. For the user, the most salient distinction is probably this: pip installs python packages within any environment; conda installs any package within conda environments. If all you are doing is installing Python packages within an isolated environment, conda and pip+virtualenv are mostly interchangeable, modulo some difference in dependency handling and package availability. By isolated environment I mean a conda-env or virtualenv, in which you can install packages without modifying your system Python installation.

Even setting aside Myth #2, if we focus on just installation of Python packages, conda and pip serve different audiences and different purposes. If you want to, say, manage Python packages within an existing system Python installation, conda can't help you: by design, it can only install packages within conda environments. If you want to, say, work with the many Python packages which rely on external dependencies (NumPy, SciPy, and Matplotlib are common examples), while tracking those dependencies in a meaningful way, pip can't help you: by design, it manages Python packages and only Python packages.

Conda和pip不是竞争对手，而是专注于不同用户组和使用模式的工具。