Permission 755 or 777?

[chup]

- when i try to upload my working file from local (xampp) to server, the images won't show, i did some research on the forum and found out that there is some folder that i need to change the permission to

Write permissions on files and folders:

/config
/tools/smarty/compile
/tools/smarty/cache
/tools/smarty_v2/compile
/tools/smarty_v2/cache
/sitemap.xml

Write permissions on folders and subfolders/recursively:

/img
/mails
/modules
/themes/prestashop/lang
/themes/prestashop/cache
/translations
/upload
/download

this is also stated is the official WIKI that permission msut be set to 777
http://www.prestashop.com/wiki/Installing_and_Updating_PrestaShop_software/


- however, other post suggest that 777 is insecure and might casue problem in the long run, so 755 should be more then enough


so which permission should those folder be eventually set to?

[chup]

bump, anyone have any idea on this?