File system setup for images

Hi,

I am creating a site that allows people to sign up for an account and post images.  These images then can be seen by everyone (member or not).  My 1st question is should I create a folder for each member to store his/her images?  2nd, and most important, if my site is setup like: ROOT\IMG and ROOT\MEMBERS\[SUB FOLDERS], where should I put the folder that going to store the images?  I'm asking because the MEMBERS and any of it's sub foldesr can only be accessed by members; so if I store images under there, will people be able to see those images if there is a link to them on the home page?    Something like Flicker would be a close example of what I'm talking about?

Thanks in advance to anyone willing to help me out.

 

 

 
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