Programs folder

• /bin: exec for all users
• /sbin: exec for admins only
• /lib: lib for programs

System folders

• /boot: for system boot
• /usr: for all non essential files to system running. example: GUI
• /usr/local: folder that is not impacted when system upgrades. Used to store manually compiled programs
• /opt: optional programs installed by packages
• /etc: editable text configuration. Configuration files
• /srv: should contain services data. not respected

users data folder

• /home/XXX: data for user XXX
• /root: home for root user

Variable data

• /var: for logs, mail
• /tmp: temp files

Mount folders

• /mnt : for mounting tempo FS. Example: /mnt/data, /mnt/samba
• /media: mount folder for removable media: USB stick...

Virtual FS

• /dev
• /proc

Linux hard drives naming

• floppy: /dev/fdX
• fake hd: /dev/loopX
• CD,DVD: /dev/srX
• IDE: /dev/hdX
• SATA: same as SCSI
• SCSI: /dev/sdX

Linux material command

• free: for memory information
• uname: material information

see dedicated virtual FS such as : /dev, /proc...

Special pseudo drives

• /dev/null: black hole
• /dev/zero: returns zeros
• /dev/full: emulate a full hard drive

About linux kernel

The kernel gives a material abstraction layer to software layer.

About linux kernel modules

The linux kernel is monolithic but some modules can be loaded/unloaded such as driver

• lsmod : list kernel modules
• modprobe: load/unload/manage kernel modules