Explanation of the Linux (Ubuntu) file system

The linux filesystem is simple and intuitive - much more so than that of Windows.  But sometimes those abbreviations are unclear.  Here's an explanation of the folder you should see in the root of your drive ("/"):

/bin – binary applications (most of your executable files)
/boot – files required to boot (such as the kernel, etc)
/dev – your devices (everything from drives to displays)
/etc – just about every configuration file for your system
/home – locally stored user files and folders
/lib – system libraries (similar to Program Files)
/lost+found – lost and found for lost files
/media – mounted (or loaded) devices such as cdroms, digital cameras, etc.
/mnt – mounted file systems
/opt – location for “optionally” installed programs
/proc – dynamic directory including information about and listing of processes
/root – “home” folder for the root user
/sbin – system-only binaries (see /bin)
/sys – contains information about the system
/tmp – temporary files
/usr – applications mainly for regular users
/var – mainly logs, databases, etc.

Note that to the beginner/regular user, most of these folders will remain untouched, with the exception of /home.  The /home directory contains folders for each user, in which _your_ specific documents, photos, video, etc. will be.  This is similar to C:/Documents and Settings/USERNAME/ you see in Windows.