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<h1>Web Servers</h1>

<p>Web servers respond to

<a class="reference external" href="http://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol">Hypertext Transfer Protocol (HTTP)</a>

requests from

clients. A client is usually a browser such as Internet Explorer, Firefox,

or Chrome, but it can also be a</p>

<ul class="simple">

<li>headless browser, which is commonly use for testing, such as

<a class="reference external" href="http://phantomjs.org/">phantomjs</a></li>

<li>commandline utility like <a class="reference external" href="https://www.gnu.org/software/wget/">wget</a>

or <a class="reference external" href="http://curl.haxx.se/">curl</a></li>

<li>a text-based web browser such as

<a class="reference external" href="http://en.wikipedia.org/wiki/Lynx_(web_browser)">Lynx</a></li>

<li>web crawler.</li>

<p>Web server process requests from the above clients. The result of the web

server's processing is a

<a class="reference external" href="https://developer.mozilla.org/en-US/docs/HTTP/Response_codes">response code</a>

and commonly a content response. Some status codes, such as 204 (No content)

and 403 (Forbidden), do not have content responses.</p>

<p>In a simple case, the client will request a static asset such as a picture

or JavaScript file. The file sits on the file system in a location the

web server is authorized to access and the web server sends the file

to the client with a 200 status code. If the client already requested the

file and the file has not changed, the web server will pass back a 304

&quot;Not modified&quot; response indicating the client already has the latest version

of that file.</p>

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<p>A web server sends files to a web browser based on the web browser's

request. In the first request, the browser accessed the

&quot;www.fullstackpython.com&quot;

address and the server responded with the index.html HTML-formatted file.

That HTML file contained references to other files, such as style.css and

script.js that the browser then requested from the server.</p>

<p>Sending static assets (such as CSS and JavaScript files) can eat up a

large amount of bandwidth which is why using a Content Delivery Network

(CDN) is important when possible (see the content delivery network

section for a more detailed explanation).</p>

<div class="section" id="web-server-resources">

<h2>Web Server Resources</h2>

<p><a class="reference external" href="http://arstechnica.com/gadgets/2012/11/how-to-set-up-a-safe-and-secure-web-server/">How to set up a safe and secure Web server</a></p>

<p><a class="reference external" href="http://library.linode.com/web-servers/apache/mod-wsgi/ubuntu-10.04-lucid">Apache and mod_wsgi on Ubuntu 10.04</a></p>

<p><a class="reference external" href="http://articles.slicehost.com/nginx">Nginx web server tutorials</a></p>

<p><a class="reference external" href="http://carrot.is/coding/nginx_introduction">Nginx for Developers: An Introduction</a></p>

<p><a class="reference external" href="http://tautt.com/best-nginx-configuration-for-security/">Nginx security configuration example</a></p>

<p><a class="reference external" href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html">HTTP Status Codes</a></p>

<p><a class="reference external" href="http://blog.zachorr.com/nginx-setup/">Battle ready Nginx - an optimization guide</a></p>

<p><a class="reference external" href="http://arstechnica.com/business/2011/11/a-faster-web-server-ripping-out-apache-for-nginx/">A faster Web server: ripping out Apache for Nginx</a></p>

<p><a class="reference external" href="http://ibuildings.nl/blog/2013/03/4-http-security-headers-you-should-always-be-using">4 HTTP Security Headers You Should Always Be Using</a></p>

<br/>

Next read the

<a href="/platform-as-a-service.html">platform-as-a-service</a> section.

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<a href="/introduction.html" class="list-group-item ">Introduction</a>

<a href="/servers.html" class="list-group-item ">Servers</a>

<a href="/operating-systems.html" class="list-group-item ">Operating Systems</a>

<a href="/web-servers.html" class="list-group-item active">Web Servers</a>

<a href="/platform-as-a-service.html" class="list-group-item ">Platform-as-a-service</a>

<a href="/databases.html" class="list-group-item ">Databases</a>

<a href="/wsgi-servers.html" class="list-group-item ">WSGI Servers</a>

<a href="/web-frameworks.html" class="list-group-item ">Web Frameworks</a>

<a href="/task-queues.html" class="list-group-item ">Task Queues</a>

<a href="/static-content.html" class="list-group-item ">Static Content</a>

<a href="/caching.html" class="list-group-item ">Caching</a>

<a href="/web-browsers.html" class="list-group-item ">Web Browsers</a>

<a href="/web-application-security.html" class="list-group-item ">Web Application Security</a>

<a href="/monitoring.html" class="list-group-item ">Monitoring</a>

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<a href="/api-integration.html" class="list-group-item ">API Integration</a>

<a href="/source-control.html" class="list-group-item ">Source Control</a>

<a href="/configuration-management.html" class="list-group-item ">Configuration Management</a>

<a href="/dependency-management.html" class="list-group-item ">Application Dependencies</a>

<a href="/no-sql-datastore.html" class="list-group-item ">NoSQL Data Stores</a>

<a href="/about-author.html" class="list-group-item ">About</a>

<a href="/change-log.html" class="list-group-item ">Change Log</a>

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