Apache is the state-of-the-art web server of the present day.
No other web server has been installed on such a large number
of hosts. No other web server has been written so many
extensions and utilities for. No other web server has been
praised that much. There must be something special about it.
Indeed, there is. Apache is powerful, but still light-weight,
it is feature-rich from basement to roof (maybe even beyond
that), but still easy to maintain and control, it is extensible,
but still self-contained, and, best of all, it is completely
free. Apache may be obtained and used at no costs, nor need
its users wonder, whether they are allowed to modify it
according to their needs. To respond to the latter question:
they are allowed to modify it; they are even encouraged to
do so. Apache is free software, Open Source to be more
precisely, and is distributed under the terms of the
Apache Software License.
Current versions of Apache are rock-solid and the respective
servers have hardly any down times or outages. Interesting
enough, Apache suffers from less vulnerabilities and
exploits than other software of the same scale of distribution,
such as
Sendmail
or
WU-FTPd.
The core web server capabilities may be easily extended
by well-known modules, such as the Secure Socket Layer
implementation
OpenSSL
as well as scripting languages like
PHP
and
mod_perl.
It is hardly conceivable that there is an task Apache,
in conjunction with some extension or module, is unable
to deal with properly.