1. STUFF
    1. initiatess
    2. monitoring
    3. stopping
    4. SHELL
      1. DEF
        1. user access system through shell
        2. Bourne Again Shell for Linux
  2. UNIX DESIGN PRINCIPLE
    1. POWER OF 3
    2. OWNERSHIP
      1. /etc/group
      2. AUTHORITY
        1. read
        2. write
        3. execute
      3. ROLE
        1. user
        2. group
          1. a category of owners
          2. share same characteristics
          3. access to limited data
        3. other
  3. ACCOUNTS
    1. process
    2. user
    3. eg:
      1. Root
        1. can do everything
        2. lost password -> need to recover with Live Linux
    4. /etc/passwd
      1. premium:x:1000:1000:Hahn Do:/home/premium:/bin/bash
      2. composition
        1. user login ID
        2. user password
        3. user ID
        4. group ID
        5. user details
        6. home directory
        7. shell
    5. /etc/shadow
      1. the major security file
        1. details of all accounts
        2. the cypher text of their passwords
    6. logs into the system
      1. must have an account
      2. logging in is controlled
  4. File System
    1. key factors
      1. file system type
      2. blocking factor
      3. device where file system is located
    2. devices at /dev
      1. /dev/sda1
      2. /dev/fd0
      3. /dev/cdrom
      4. .....
    3. manipulate
      1. create
        1. mkfs
      2. mount
        1. mount
        2. unmount
        3. /etc/mtab
          1. list of currently mounted file systems
        4. /etc/fstab
          1. list of file systems to be automatically mounted at boot time
        5. Command syntax
      3. find
    4. file attributes
      1. DEF
        1. xxxx aAAABBBCCC # owner group size date time name
      2. manipulate
        1. ?
          1. touch
        2. chmod
          1. change file ownership
          2. change group association
          3. change security attribute