The Httpd Web Server, commonly referred to as Apache , is web server software outstanding for the purpose playing a pivotal role in the initial broadening of the Society Big Web. In 2009 it became the first cobweb server software to best the 100 million website milestone. Apache was the beginning practicable alternative to the Netscape Communications Corporation cobweb server (currently known as Message iPlanet Snare Server), and has since evolved to compete with other trap servers in terms of functionality and performance. Typically Apache is run on a Unix-like operating system.
Apache is developed and maintained by way of an open community of developers second to the auspices of the Apache Software Foundation. The utilization is ready for a wide selection of operating systems, including Unix, GNU, FreeBSD, Linux, Solaris, Novell NetWare, AmigaOS, Mac OS X, Microsoft Windows, OS/2, TPF, and eComStation. Released supervised the Apache Accredit, 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 accommodate 63% of all websites and 66% of the million busiest.
Features

Apache supports a variety of features, tons implemented as compiled modules which on the pit functionality. These can latitude from server-side programming language stick up for to authentication schemes. Some common language interfaces support Perl, Python, Tcl, and PHP. Popular authentication modules take in mod_access, mod_auth, mod_survive, and mod_auth_digest, the successor to mod_digest. A illustration of other features classify SSL and TLS help (mod_ssl), a factor module (mod_substitute), a URL rewriter (also known as a rewrite engine, implemented supervised mod_rewrite), routine log files (mod_log_config), and filtering support (mod_include and mod_ext_filter).
Popular compression methods on Apache categorize the exotic augmentation module, mod_gzip, implemented to help with reduction of the size (ballast) of snare pages served over HTTP. ModSecurity is an available begetter intrusion detection and prevention apparatus for web applications. Apache logs can be analyzed help of a entanglement browser using sprung scripts such as AWStats/W3Perl or Visitors.
Virtual hosting allows united Apache installation to serve many diverse physical websites. Allowing for regarding example, joined gizmo with harmonious Apache ordination could simultaneously favourable to www.example.com, www.test.com, test47.test-server.test.com, etc.
Apache features configurable error messages, DBMS-based authentication databases, and constituents negotiation. It is also supported not later than disparate graphical user interfaces (GUIs).
It supports open sesame authentication and digital certificate authentication. Apache has a built in search engine and an HTML authorizing contraption and supports FTP.

Exhibit


This portion does not cite any references or sources. Please cure repair this leg through adding citations to reliable sources. Unsourced figures may be challenged and removed. (October 2009)
Although the sheer design object of Apache is not to be the "fastest" trap server, Apache does take fulfilment comparable to other "high-performance" trap servers. A substitute alternatively of implementing a individual architecture, Apache provides a heterogeneity of MultiProcessing Modules (MPMs) which allow Apache to hump it in a process-based, hybrid (process and motif) or event-hybrid set-up, to superior meet the demands of each separate infrastructure. This implies that the preference of chasten MPM and the correct configuration is important. Where compromises in doing need to be made, the conceive of Apache is to belittle latency and augment throughput, dependent on to obviously handling more requests, consequently ensuring predictable and reliable processing of requests within logical time-frames.
The Apache translation considered by means of the Apache Base as providing high-performance is the multi-threaded adaptation which mixes the utilize consume of a handful processes and diverse threads per process.
While this architecture works faster than the previous multi-process based topology (because threads have a deign upper basic than processes), it does not copy the performances of the event-based architecture provided sooner than other servers, uncommonly when they process events with respective hand threads.
This distinction can be without even trying explained by the overhead that a man thread per relevance brings (as opposed to a couple of breadwinner threads per CPU, each processing diverse drag relatives events). Each thread needs to keep going its own chimney, habitat, and switching from in unison thread to another is also an high-priced censure for CPUs.