Q: What are the different folders in my ftp directory for?

htdocs	Place your website files here. Typically all your html, asp, gif and jpeg files, amongst others. Copy your site, including all it's folders into this folder.
logfiles	We give you full unrestricted access to your logfiles. Whenver a visitor accesses your website, a record of the files and images and requests are stored in the logfiles. There are many free applications availalbe that can analyse the logfiles to show you your site usage statistics. Your can even access your logfiles via script.
private	Put your sensitive data here. You can create additional folders in this folder to put your databases, and use the DNS wizard to give you secure access to your databases.