1. / (Root Directory)

The top-level directory of the filesystem. All other directories are subdirectories of the root directory.

• Files and Directories: Contains system directories like bin, etc, home, lib, usr, etc.

2. /bin (Binaries)

Contains essential binary executables.

• Files: System binaries needed for basic functionality.
• Examples: ls, cp, mv, bash.

3. /boot

Contains the files needed to boot the system.

• Name: "boot" comes from the process of bootstrapping, which is loading the operating system.
• Files: Kernel images, bootloader files.
• Examples: vmlinuz, initrd.img, grub.

4. /dev (Devices)

Contains device files.

• Files: Special files that represent hardware devices.
• Examples: sda, tty, null.

5. /etc (Etcetera)

Contains configuration files.

• Name: "etc" originally stood for etcetera, a place to store configuration files.
• Files: System-wide configuration files.