HFS: The Virtual File System
Ok, from the beginning...
What is a File
It is a sequence of bytes. A byte is a unit of information.
What is a File System
It is an ordered set of files. Often they are hierarchically ordered, in folders (also called directories).
What is a Virtual File System
File Systems usually lie on a disk. A Virtual File System (VFS from now on) does lie in memory instead. This can be a very interesting thing, in facts this is the main reason I started working on HFS.
Thanks to the VFS you can publish things in the way you want without changing anything on your disk. People will see what you want them to see. You can hide files, rename them, move 'em to another folder...well, this is what people will see! Nothing changes on your disk.
A lot of people is already experienced in that, because of well-known softwares, like Nero, has a VFS, where you can project your CD. With HFS you project...your website.
Most web servers let you publish one or more folders, but the content shown will just reflect the disk. This is often an unwanted feature.
What is a real/virtual folder
The VFS in HFS has both virtual folders and real folders. Sometimes it may be the same to you, other times you'd better pay attention on what you choose.
Virtual folders are yellow, real folders are red.
A real folder is a link to a folder on your disc, and will show the current (real-time) content of your disc.
Anyway, the real folder is not necessarily as the folder on your disc. There are many aspects of the folder that you can change virtually. You can rename it, add files, hide files...many things.
A virtual folder will show only items you see in the VFS. When you add a virtual folder based on a folder of your disc, the content of the disc is copied in the VFS. From now on, the content is detached from the disc, it is virtualized. If in the while a file is added or removed, the VFS won't be updated.