GRUB/ROOT/unmount/eject

[thera]

Can someone explain to me what GRUB and ROOT are?
What do they do?
I am a bit of a Linux noob.

In LL 2.0 What is the difference between unmounting and ejecting a usb flash drive?
Which is safer to do before the flash drive is physically removed from the usb port?

[shengchieh]

Root is one file component, i.e., /root.  There are alot of others.  See

File Structures and Types
http://www.debianadmin.com/linux-directo...rview.html (Linux Directory Structure Overview; 3/23/08)
http://en.wikipedia.org/wiki/Comparison_of_file_systems (Comparison of file systems) (Comparison of file systems; current)
http://omnitraining.net/free-articles/19...ermissions (Back to Basics: Unix File Permissions; 2/17/10)
http://www.junauza.com/2009/03/important...-that.html (Important Linux File Directories That Users Should Know About; 3/5/09)
http://www.nixtutor.com/linux/understand...ry-layout/ (Understanding the Linux Directory Layout; 2/5/09)
http://www.ibm.com/developerworks/linux/...index.html (Learn Linux, 101: Find and place system files; 6/9/10)
http://www.ibm.com/developerworks/linux/...index.html (Learn Linux, 101: Maintain the integrity of filesystems; 8/24/10)
http://www.linuxbsdos.com/2011/09/18/gui...-in-linux/ (Guide to disks and disk partitions in Linux; 9/18/11)
http://www.howtogeek.com/117435/htg-expl...explained/ (HTG Explains: The Linux Directory Structure Explained; 6/25/12)
http://www.tecmint.com/linux-directory-s...explained/ (Linux Directory Structure and Important Files Paths Explained; 9/16/13)

Grub is a bootloader.  There are others.  See

BootLoader
http://www.gnu.org/software/grub/ (non-commercial; Grub)

USB flash drive can't be ejected.  You have to physically remove them.  But CD/DVD can be ejected or unmounted.  The difference is the media is out of the computer vs just " out of the system".
It is good practice to unmounted or eject before removing an external device.  I do NOT know how LL works (someone else?) - some distros do it automatically - other distros don't - so I just do it
to avoid any mishap.

Sheng-Chieh

[gold_finger]

Root is the term for the base of the file system, off of which everything else is branched.  All of the main system directories are sub-directories off of root.  The symbol for root is a single forward slash "/".  Home is depicted as "/home" -- which you could read as "root" - "home".  shengchieh provided some very good information links.  Definitely take the time to read through some of those -- it will be worth your time.

Regarding other issue, here is a good post to look through:  What is the difference between “Unmount”, “Eject”, “Safely Remove Drive” and the eject icon?

[N4RPS]

Hello!

"Root" also refers to the root user - the one who can edit the user accounts of others, imstall and remove software, and work with files that reside outside a user's 'home' directory...

73 DE N4RPS
Rob