Linux File System

In Linux, the File system is in a hierarchical tree structure. It contains one root folder ( / ). In Linux, data is stored in formats like EXT3, EXT4, BTRFS, XFS, and so on

/root/

/root/ is the root user's home directory

/home/

/home/ contains the home directory of all non-root users

/home/username

the home directory of a particular user. By default, it contains folders like Desktop, Documents, Downloads, Music, Pictures, Template, Videos.

• each user has its own space.
• each user can have its own configuration.
• multiple users can work on its computer
• programs installed system-wide are available for all users on the computer

/bin/

/bin/ contains binaries.

• Executable for most essential user commands like cat, cp, echo,.., etc.,
• there are all available system-wide
• What are binaries? Computer-readable format

/sbin/

/sbin/ contains system binaries.

• these binaries are different from /bin/ binaries
• these commands are system-related
• these commands need superuser privilege like adduser, etc
• What are system binaries? essential system binaries. programs that admin would use (need superuser privilege )

/lib/

/lib/ contains libraries.

• essential shared library that executable from /bin/ or /sbin/

/usr/

/usr/ was used for user home directories.

• It contains folders like bin (same as /bin/ content), games, include, lib, lib32, lib64, lib, local, sbin (same as /sbin/ content), share, src
• because of storage limitations it was split to the root binary folder and usr binary folder
• split doesn't make sense now, as the concept stays the same

/usr/local/

• programs installed here, will be available for all users on the computer
• program which splits its components are installed here

For example we installed java

• binary files goes to /usr/local/bin
• library files goes to /usr/local/lib
• documentation
• configuration

/home/

programs installed here are available for specific users only

/opt/

• optional - third party programs that we install
• empty for a new install
• available to all users
• mostly code editors and web browsers installed in /opt/ directory
• program which wont splits its components are installed here

/boot/

• booting - contains files required for booting

/etc/

• etcetera - contains configuration files for system-wide applications
• It contains system configurations, network configurations, user data, and passwords

/dev/

• devices - contains device files for devices like webcam, keyboard, hard disk etc
• Applications and Drivers will access this directory NOT the user

/var/

• variable - contains files to which the system writes data during the course of its operation

• /var/log/ - contains log file
• /var/cache / - contains cache data from application programs

/tmp/

• temporary - temporary resources required for some process, kept here temporarily

/media/

• removable media - contains subdirectories where removable media devices inserted into the computer are mounted

/mnt/

• temporary mount points - historically sysadmins used to mount temporary files system here
• to manually mount a device to the system then we use /mnt/ folder