Optimizing Website Speed and Caching

.htaccess

<IfModule pagespeed_module>
    ModPagespeed on
    # using commands,filters etc
</IfModule>

<ifModule mod_deflate.c>
    AddOutputFilterByType DEFLATE text/html text/plain text/xml application/xml application/xhtml+xml text/css text/javascript application/javascript application/x-javascript
</ifModule>

# BEGIN Expire headers
<IfModule mod_expires.c>
ExpiresActive On
ExpiresByType image/jpg "access 1 year"
ExpiresByType image/jpeg "access 1 year"
ExpiresByType image/gif "access 1 year"
ExpiresByType image/png "access 1 year"
ExpiresByType text/css "access 1 month"
ExpiresByType text/html "access 1 month"
ExpiresByType application/pdf "access 1 month"
ExpiresByType text/x-javascript "access 1 month"
ExpiresByType text/javascript "access 1 month"
ExpiresByType application/javascript "access 1 month"
ExpiresByType application/x-javascript "access 1 month"
ExpiresByType application/x-shockwave-flash "access 1 month"
ExpiresByType image/x-icon "access 1 year"
ExpiresDefault "access 1 month"
</IfModule>
# END Expire headers

# BEGIN Cache-Control Headers
<ifModule mod_headers.c>
    <filesMatch "\.(ico|jpe?g|png|gif|swf)$">
        Header set Cache-Control "public"
    </filesMatch>
    <filesMatch "\.(css)$">
        Header set Cache-Control "public"
    </filesMatch>
    <filesMatch "\.(js)$">
        Header set Cache-Control "private"
    </filesMatch>
    <filesMatch "\.(x?html?|php)$">
        Header set Cache-Control "private, must-revalidate"
    </filesMatch>
</ifModule>
# END Cache-Control Headers

Header unset Pragma
FileETag None
Header unset ETag

<IfModule mod_gzip.c>
mod_gzip_on Yes
mod_gzip_dechunk Yes
mod_gzip_item_include file \.(html?|txt|css|js|php|pl)$
mod_gzip_item_include handler ^cgi-script$
mod_gzip_item_include mime ^text/.*
mod_gzip_item_include mime ^application/x-javascript.*
mod_gzip_item_exclude mime ^image/.*
mod_gzip_item_exclude rspheader ^Content-Encoding:.*gzip.*
</IfModule>