<p>This command installs a package, and any packages that it depends on.</p>
<p>A <code>package</code> is:</p>
<ul><li>a) a folder containing a program described by a package.json file</li><li>b) a gzipped tarball containing (a)</li><li>c) a url that resolves to (b)</li><li>d) a <code><name>@<version></code> that is published on the registry with (c)</li><li>e) a <code><name>@<tag></code> that points to (d)</li><li>f) a <code><name></code> that has a "latest" tag satisfying (e)</li><li>g) a <code><git remote url></code> that resolves to (b)</li></ul>
<p>Even if you never publish your package, you can still get a lot of
benefits of using npm if you just want to write a node program (a), and
perhaps if you also want to be able to easily install it elsewhere
after packing it up into a tarball (b).</p>
<ul><li><p><code>npm install</code> (in package directory, no arguments):
Install the dependencies in the local node_modules folder.</p><p>In global mode (ie, with <code>-g</code> or <code>--global</code> appended to the command),
it installs the current package context (ie, the current working
directory) as a global package.</p></li><li><p><code>npm install <folder></code>:
Install a package that is sitting in a folder on the filesystem.</p></li><li><p><code>npm install <tarball file></code>:
Install a package that is sitting on the filesystem. Note: if you just want
to link a dev directory into your npm root, you can do this more easily by
using <code>npm link</code>.</p><p>Example:</p><pre><code>npm install ./package.tgz</code></pre></li><li><p><code>npm install <tarball url></code>:
Fetch the tarball url, and then install it. In order to distinguish between
this and other options, the argument must start with "http://" or "https://"</p><p>Example:</p><pre><code>npm install https://github.com/indexzero/forever/tarball/v0.5.6</code></pre></li><li><p><code>npm install <name></code>:
Do a <code><name>@<tag></code> install, where <code><tag></code> is the "tag" config. (See
<code><ahref="../doc/config.html">config(1)</a></code>)</p><p>Example:</p><pre><code>npm install sax</code></pre><p><strong>Note</strong>: If there is a file or folder named <code><name></code> in the current
working directory, then it will try to install that, and only try to
fetch the package by name if it is not valid.</p></li><li><p><code>npm install <name>@<tag></code>:
Install the version of the package that is referenced by the specified tag.
If the tag does not exist in the registry data for that package, then this
will fail.</p><p>Example:</p><pre><code>npm install sax@latest</code></pre></li><li><p><code>npm install <name>@<version></code>:
Install the specified version of the package. This will fail if the version
has not been published to the registry.</p><p>Example:</p><pre><code>npm install sax@0.1.1</code></pre></li><li><p><code>npm install <name>@<version range></code>:
Install a version of the package matching the specified version range. This
will follow the same rules for resolving dependencies described in <code><ahref="../doc/json.html">json(1)</a></code>.</p><p>Note that most version ranges must be put in quotes so that your shell will
treat it as a single argument.</p><p>Example:</p><pre><code>npm install sax@">=0.1.0 <0.2.0"</code></pre></li><li><p><code>npm install <git remote url></code>:</p><p>Install a package by cloning a git remote url. The format of the git
url is:</p><pre><code><protocol>://[<user>@]<hostname><separator><path>[#<commit-ish>]</code></pre><p><code><protocol></code> is one of <code>git</code>, <code>git+ssh</code>, <code>git+http</code>, or
<code>git+https</code>. If no <code><commit-ish></code> is specified, then <code>master</code> is
