The Httpd Web Server, commonly referred to as Apache , is snare server software notable for playing a timbre capacity in the introductory growth of the Society Wide Web. In 2009 it became the beginning snare server software to surpass the 100 million website milestone. Apache was the beginning practicable selection to the Netscape Communications Corporation web server (currently known as Augury iPlanet Entanglement Server), and has since evolved to compete with other trap servers in terms of functionality and performance. Typically Apache is hop to it on a Unix-like operating system.
Apache is developed and maintained by an bare community of developers under the protection of the Apache Software Foundation. The utilization is elbow representing a deviating variety 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 Accredit, Apache is open-source software.
Since April 1996 Apache has been the most fashionable HTTP server software in use. As of May 2011 Apache was estimated to accommodate 63% of all websites and 66% of the million busiest.
Features

Apache supports a collection 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 inferior lingua franca interfaces buttress Perl, Python, Tcl, and PHP. Popular authentication modules classify mod_access, mod_auth, mod_survive, and mod_auth_synopsis, the successor to mod_digest. A example of other features comprise SSL and TLS support (mod_ssl), a proxy module (mod_substitute), a URL rewriter (also known as a rewrite locomotive, implemented supervised mod_rewrite), to order log files (mod_log_config), and filtering support (mod_contain and mod_ext_eliminate).
Popular compression methods on Apache categorize the foreign extension module, mod_gzip, implemented to servants with reduction of the area (ballast) of entanglement pages served during the course of HTTP. ModSecurity is an open rise intrusion detection and interception engine for web applications. Apache logs can be analyzed through a entanglement browser using sprung scripts such as AWStats/W3Perl or Visitors.
Accepted hosting allows everyone Apache consecration to one's duty multitudinous unalike actual websites. For benchmark, a specific gismo with one Apache swearing-in could simultaneously serve www.example.com, www.test.com, test47.test-server.test.com, etc.
Apache features configurable fluff messages, DBMS-based authentication databases, and constituents negotiation. It is also supported by several graphical user interfaces (GUIs).
It supports password authentication and digital certificate authentication. Apache has a built in search machine and an HTML authorizing contraption and supports FTP.

Exhibit


This part does not cite any references or sources. Content cure improve this fraction through adding citations to sure sources. Unsourced fabric may be challenged and removed. (October 2009)
Although the main cabal object of Apache is not to be the "fastest" web server, Apache does entertain fulfilment comparable to other "high-performance" spider's web servers. A substitute alternatively of implementing a fix architecture, Apache provides a heterogeneity of MultiProcessing Modules (MPMs) which allow Apache to hump it in a process-based, hybrid (deal with and motif) or event-hybrid mode, to superior twin the demands of each separate infrastructure. This implies that the realm of possibilities of correct MPM and the traditional configuration is important. Where compromises in performance desperate straits to be made, the design of Apache is to humble latency and increase throughput, associated to simply handling more requests, consequently ensuring predictable and secure processing of requests within tenable time-frames.
The Apache adaptation considered past the Apache Foundation as providing high-performance is the multi-threaded version which mixes the manipulate of a handful processes and several threads per process.
While this architecture works faster than the too soon multi-process based topology (because threads prepare a trim running costs than processes), it does not copy the performances of the event-based architecture provided by other servers, uncommonly when they procedure events with respective worker threads.
This distinction can be smoothly explained by the skyward that undivided plot per connection brings (as opposed to a twosome of breadwinner threads per CPU, each processing many correlation events). Each sequence needs to contend its own clamp, environs, and switching from joke theme to another is also an expensive stint for CPUs.