How do I read .htaccess file? - .htaccess

Question

I've got this gigantic .htaccess file, and I believe it prevents users not on the local network from accessing a given site.
I am trying to interpret it, but the only part I know of that would limit access is the order allow, deny portion, and I don't see anything that I would suspect is external IPs.
Here's the code:
#
# Apache/PHP/Drupal settings:
#
# Protect files and directories from prying eyes.
<FilesMatch "\.(engine|inc|info|install|make|module|profile|test|po|sh|.*sql|theme|tpl(\.php)?|xtmpl|svn-base)$|^(code-style\.pl|Entries.*|Repository|Root|Tag|Template|all-wcprops|entries|format)$">
Order allow,deny
</FilesMatch>
# Don't show directory listings for URLs which map to a directory.
Options -Indexes
# Follow symbolic links in this directory.
Options +FollowSymLinks
# Make Drupal handle any 404 errors.
ErrorDocument 404 /index.php
# Force simple error message for requests for non-existent favicon.ico.
<Files favicon.ico>
# There is no end quote below, for compatibility with Apache 1.3.
ErrorDocument 404 "The requested file favicon.ico was not found.
</Files>
# Set the default handler.
DirectoryIndex index.php
# Override PHP settings. More in sites/default/settings.php
# but the following cannot be changed at runtime.
# PHP 4, Apache 1.
<IfModule mod_php4.c>
php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0
</IfModule>
# PHP 4, Apache 2.
<IfModule sapi_apache2.c>
php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0
</IfModule>
# PHP 5, Apache 1 and 2.
<IfModule mod_php5.c>
php_value magic_quotes_gpc 0
php_value register_globals 0
php_value session.auto_start 0
php_value mbstring.http_input pass
php_value mbstring.http_output pass
php_value mbstring.encoding_translation 0
</IfModule>
# Requires mod_expires to be enabled.
<IfModule mod_expires.c>
# Enable expirations.
ExpiresActive On
# Cache all files for 2 weeks after access (A).
ExpiresDefault A1209600
<FilesMatch \.php$>
# Do not allow PHP scripts to be cached unless they explicitly send cache
# headers themselves. Otherwise all scripts would have to overwrite the
# headers set by mod_expires if they want another caching behavior. This may
# fail if an error occurs early in the bootstrap process, and it may cause
# problems if a non-Drupal PHP file is installed in a subdirectory.
ExpiresActive Off
</FilesMatch>
</IfModule>
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
# If your site can be accessed both with and without the 'www.' prefix, you
# can use one of the following settings to redirect users to your preferred
# URL, either WITH or WITHOUT the 'www.' prefix. Choose ONLY one option:
#
# To redirect all users to access the site WITH the 'www.' prefix,
# (http://example.com/... will be redirected to http://www.example.com/...)
# adapt and uncomment the following:
# RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
# RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]
#
# To redirect all users to access the site WITHOUT the 'www.' prefix,
# (http://www.example.com/... will be redirected to http://example.com/...)
# uncomment and adapt the following:
# RewriteCond %{HTTP_HOST} ^www\.example\.com$ [NC]
# RewriteRule ^(.*)$ http://example.com/$1 [L,R=301]
# Modify the RewriteBase if you are using Drupal in a subdirectory or in a
# VirtualDocumentRoot and the rewrite rules are not working properly.
# For example if your site is at http://example.com/drupal uncomment and
# modify the following line:
# RewriteBase /drupal
#
# If your site is running in a VirtualDocumentRoot at http://example.com/,
# uncomment the following line:
# RewriteBase /
# Rewrite URLs of the form 'x' to the form 'index.php?q=x'.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !=/favicon.ico
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]
</IfModule>
# $Id$

Answer 1

# Protect files and directories from prying eyes.
<FilesMatch "\.(engine|inc|info|install|make|module|profile|test|po|sh|.*sql|theme|tpl(\.php)?|xtmpl|svn-base)$|^(code-style\.pl|Entries.*|Repository|Root|Tag|Template|all-wcprops|entries|format)$">
Order allow,deny
</FilesMatch>
Matches the extentions in brackets and set Allow/Disallor-Order
# Don't show directory listings for URLs which map to a directory.
Options -Indexes
As the comment says
# Follow symbolic links in this directory.
Options +FollowSymLinks
As the comment says
# Make Drupal handle any 404 errors.
ErrorDocument 404 /index.php
Sets the Document which is shown after a 404 (Not Found) Error
# Force simple error message for requests for non-existent favicon.ico.
<Files favicon.ico>
# There is no end quote below, for compatibility with Apache 1.3.
ErrorDocument 404 "The requested file favicon.ico was not found.
</Files>
favicon.ico gets a special 404-error page
# Set the default handler.
DirectoryIndex index.php
You request "/" which file has to be displayed
# Override PHP settings. More in sites/default/settings.php
# but the following cannot be changed at runtime.
As it says
# Requires mod_expires to be enabled.
<IfModule mod_expires.c>
# Enable expirations.
ExpiresActive On
# Cache all files for 2 weeks after access (A).
ExpiresDefault A1209600
<FilesMatch \.php$>
# Do not allow PHP scripts to be cached unless they explicitly send cache
# headers themselves. Otherwise all scripts would have to overwrite the
# headers set by mod_expires if they want another caching behavior. This may
# fail if an error occurs early in the bootstrap process, and it may cause
# problems if a non-Drupal PHP file is installed in a subdirectory.
ExpiresActive Off
</FilesMatch>
</IfModule>
Enabled the cache-header, but not for *.php
# Various rewrite rules.
<IfModule mod_rewrite.c>
RewriteEngine on
# Rewrite URLs of the form 'x' to the form 'index.php?q=x'.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !=/favicon.ico
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]
</IfModule>
As the comment says: Rewrite the url, so that index.php is called.