<chapter id='introduction'><title>Introduction</title>

<section id='purpose'><title>Purpose</title>

<para>This standard enables:</para>
<itemizedlist>
<listitem>
<para>Software to predict the location of installed files and
directories, and</para>
</listitem>
<listitem>
<para>Users to predict the location of installed files and
directories.</para>
</listitem>
</itemizedlist>

<para>We do this by:</para>
<itemizedlist>
<listitem>
<para>Specifying guiding principles for each area of the filesystem,</para>
</listitem>
<listitem>
<para>Specifying the minimum files and directories required,</para>
</listitem>
<listitem>
<para>Enumerating exceptions to the principles, and</para>
</listitem>
<listitem>
<para>Enumerating specific cases where there has been historical conflict.</para>
</listitem>
</itemizedlist>

<para>The FHS document is used by:</para>
<itemizedlist>
<listitem>
<para>Independent software suppliers to create applications which are FHS
compliant, and work with distributions which are FHS compliant,</para>
</listitem>
<listitem>
<para>OS creators to provide systems which are FHS compliant, and</para>
</listitem>
<listitem>
<para>Users to understand and maintain the FHS compliance of a system.</para>
</listitem>
</itemizedlist>

<para>The FHS document has a limited scope:</para>
<itemizedlist>
<listitem>
<para>Local placement of local files is a local issue, so FHS does not
attempt to usurp system administrators.</para>
</listitem>
<listitem>
<para>FHS addresses issues where file placements need to be coordinated
between multiple parties such as local sites, distributions,
applications, documentation, etc.</para>
</listitem>
</itemizedlist>
</section>

<section id='conventions'><title>Conventions</title>

<para>We recommend that you read a typeset version of this document rather
than the plain text version.  In the typeset version, the names of files
and directories are displayed in a constant-width font.</para>

<para>Components of filenames that vary are represented by a description
of the contents enclosed in "<replaceable>&lt;</replaceable>" and
"<replaceable>&gt;</replaceable>" characters, 
<replaceable>&lt;thus&gt;</replaceable>.  Electronic mail addresses are also
enclosed in "&lt;" and "&gt;" but are shown in the usual
typeface.</para>

<para>Optional components of filenames are enclosed in
"<replaceable>[</replaceable>" and "<replaceable>]</replaceable>" characters and may
be combined with the "<replaceable>&lt;</replaceable>" and
"<replaceable>&gt;</replaceable>" convention.  For example, if a filename is
allowed to occur either with or without an extension, it might be
represented by
<replaceable>&lt;filename&gt;[.&lt;extension&gt;]</replaceable>.</para>

<para>Variable substrings of directory names and filenames are indicated
by "<replaceable>*</replaceable>".</para>

<para>The sections of the text marked as
<emphasis>Rationale</emphasis> are explanatory and are
non-normative.</para>

</section>

</chapter>
