I will briefly describe the Linux directory structure:
/
The root section.
/bin
The storage directory of the main binary user modules (programs).
/boot
Directory for storing Linux kernel images, grub bootloader.
/cdrom
CD mount point
/dev
The directory contains files of devices connected to the operating system. printers, scanners, hard drives, etc.
/etc
Directory with configuration files.
/home
Directory with user home directories.
/lib
A directory storing the system libraries necessary for the main binaries from the /bin and /sbin directories.
/lost+found
Files recovered after a crash.
/media
Directory for automatically mounting devices, such as USB drives, CD-ROMs, etc.
/mnt
Directory for manually mounting devices, such as USB sticks, CD-ROMs, etc.
/opt
Directory where helper packages are usually located.
/proc
Kernel and process files.
/root
Superuser home directory.
/run
application status files
/sbin
The storage directory of the main binary system modules (programs).
/srv
Service data. Usually the directory is empty. It may contain, for example, the /srv/ftp directory as the standard directory for ftp server files, etc.
/sys
A directory with the sysfs file system mounted, which adds Linux kernel information about devices and drivers present in the system to the user space.
/tmp
Directory for storing temporary files. All users have full access to this directory. It is automatically cleared after restarting the operating system.
/usr
Custom binaries and read-only data.
/var
Directory for frequently changing data.