How to rename already indexed files & directories

I need to rename several files and move other files to a different directory on my site. These files are already indexed in Google. I was wondering what't the best way to go around it. Would it matter if they'll be indexed twice under different name/directory, or should I use some 301 redirect or meta tag to tell Google that their name/location has changed?

 

The 301 option will get your new URI's indexed faster, and help pass PR to the new pages.

 

Google seems to prefer 301 Redirects.

 

I just changed my site from dynamic urls to static urls (it's still dynamic, I'm just using an ISAPI Rewrite filter to parse the url) and I coded the pages to generate a 301 if someone / something requests the old url which takes them to the new url. Nearly half of my site has been re-spidered and many pages have improved rank because of this.

 

Also in the same vein, I am changing from static HTML pages to PHP.

Will changing the extension from .html to .php affect my pages ranking and PR??

eg.

I will be changing

from

www.mysite.com/mypage.html

to

www.mysite.com/mypage.php

thanks

 

So I'm assuming that I have to do this for each page separately, correct?

Something like:

redirect 301 /olddirectory/oldfile.html /newdirectory/newfile.html
redirect 301 /olddirectory/oldfile2.html /newdirectory/newfile2.html
...etc...

Right?