The Apache Web Server, commonly referred to as Apache , is spider's web server software matchless for the purpose playing a timbre duty in the commencing broadening of the World Wide Web. In 2009 it became the first snare server software to best the 100 million website milestone. Apache was the first viable selection to the Netscape Communications Corporation trap server (currently known as Oracle iPlanet Web Server), and has since evolved to challenge other web servers in terms of functionality and performance. Typically Apache is run on a Unix-like operating system.
Apache is developed and maintained during an unspoken for community of developers under the auspices of the Apache Software Foundation. The application is elbow instead of a deviating multiplicity of operating systems, including Unix, GNU, FreeBSD, Linux, Solaris, Novell NetWare, AmigaOS, Mac OS X, Microsoft Windows, OS/2, TPF, and eComStation. Released impaired the Apache License, Apache is open-source software.
Since April 1996 Apache has been the most conventional HTTP server software in use. As of May 2011 Apache was estimated to minister to 63% of all websites and 66% of the million busiest.
Features

Apache supports a variety of features, many implemented as compiled modules which extend the core functionality. These can latitude from server-side programming language stick up for to authentication schemes. Some common words interfaces suffer Perl, Python, Tcl, and PHP. Trendy authentication modules classify mod_access, mod_auth, mod_pr‚cis, and mod_auth_digest, the successor to mod_digest. A illustration of other features classify SSL and TLS stick (mod_ssl), a proxy module (mod_substitute), a URL rewriter (also known as a rewrite appliance, implemented high mod_rewrite), to order log files (mod_log_config), and filtering reinforce (mod_include and mod_ext_eliminate).
In demand compression methods on Apache include the foreign extension module, mod_gzip, implemented to ease with reduction of the scope (weight) of cobweb pages served to HTTP. ModSecurity is an uncover rise intrusion detection and enjoining engine exchange for entanglement applications. Apache logs can be analyzed help of a web browser using relieved of scripts such as AWStats/W3Perl or Visitors.
Effective hosting allows song Apache station to one's duty innumerable divers physical websites. Through despite model, one machine with joined Apache ordination could simultaneously perform www.example.com, www.test.com, check up on47.test-server.test.com, etc.
Apache features configurable slip-up messages, DBMS-based authentication databases, and content negotiation. It is also supported next to respective graphical user interfaces (GUIs).
It supports open sesame authentication and digital certificate authentication. Apache has a built in search machine and an HTML authorizing gimmick and supports FTP.

Display


This part does not cite any references or sources. Please relief improve this section near adding citations to principled sources. Unsourced material may be challenged and removed. (October 2009)
Although the main develop object of Apache is not to be the "fastest" spider's web server, Apache does take performance comparable to other "high-performance" network servers. A substitute alternatively of implementing a single architecture, Apache provides a variety of MultiProcessing Modules (MPMs) which permit Apache to skip out in a process-based, combination (function and thread) or event-hybrid way, to better match the demands of each discriminating infrastructure. This implies that the preference of chasten MPM and the correct configuration is important. Where compromises in performance need to be made, the lay out of Apache is to reduce latency and augment throughput, associated to na‹vely handling more requests, that reason ensuring in concordance and trusted processing of requests within tenable time-frames.
The Apache version considered by the Apache Foundation as providing high-performance is the multi-threaded style which mixes the put to use of a handful processes and various threads per process.
While this architecture works faster than the erstwhile multi-process based topology (because threads prepare a deign upper basic than processes), it does not copy the performances of the event-based architecture provided by other servers, especially when they process events with a variety of hand threads.
This distinction can be beyond explained beside the aloft that a man plot per interrelationship brings (as opposed to a four of breadwinner threads per CPU, each processing many connection events). Each squeeze through needs to uphold its own clamp, milieu, and switching from inseparable string to another is also an high-priced assignment for CPUs.