Suggested .htaccess rewrite is not hiding system folder

[eluser]helloworldly[/eluser]
Thanks Rick. Yes, it's preventing access to system folder now, though it couldn't find the index.php:

"The requested URL /index.php was not found on this server."

So originally it was:
RewriteCond %{REQUEST_URI} ^system.*
RewriteRule ^(.*)$ /index.php?/$1 [L]

And you added this similar rule above other rules:
RewriteCond $1 ^system [NC]
RewriteRule ^(.*)$ /index.php?/$1 [L]

What's the difference between the two? Why would two rules be needed?

Thanks Rick!