/lib/usr/lib/usr/local/lib differences

USR Many people think it is the user abbreviation, not actually, is the UNIX system resource abbreviation

/lib are kernel-level,/usr/lib are system-level,/usr/local/lib are user-level.

/lib/-contains many library files that are used by programs in/bin/and/sbin/. The directory/usr/lib/contains more library files for user programs. The/lib directory is placed under the/bin and/sbin directories required by the program's library files. The name of the file under the/lib directory follows the following format:
Libc.so.*
ld*
Only shared libraries that are used by programs in the/USR directory do not have to be placed in the/lib directory. Only the libraries required for the programs under/bin and/sbin need to be placed in the/lib directory. In fact, libm.so.*-type library files can be placed under/usr/lib if they are required by/bin and/sbin.

/bin/-is used to store user commands. Directory/usr/bin is also used to store user commands.

/sbin/-the storage location of many system commands (such as shutdown). Many system commands are also included in the directory/usr/sbin.

/root/-the root user (Superuser) home directory.

/mnt/-This directory typically includes mount points for file systems that are mounted after system boot. For example, the default CD mount point is/mnt/cdrom/.

/boot/-includes the kernel and files used during startup of other systems.

/lost+found/-is used by fsck to place scattered files (files with no names).

/lib/-contains many library files that are used by programs in/bin/and/sbin/. The directory/usr/lib/contains more library files for user programs.

/dev/-Storage equipment files.

/etc/-contains many configuration files and directories.

/var/-is used to store variable (or constantly changing) files, such as log files and printer spool files.

/usr/-includes files and directories that are directly related to system users, such as applications and library files that support them.

/proc/-a virtual file system (not actually stored on disk), which includes system information that is used by some programs.

/initrd/-is used to mount the directory of the initrd.img image file when the computer starts up and the directory to load the required device modules.

Warning

Do not delete the/initrd/directory. If you delete the directory and then reboot Red Hat Linux, you will not be able to boot your computer.

/tmp/-a temporary directory for users and programs. /TMP gives all system users read and write rights.

/home/-The default location of the user's home directory.

/opt/-the storage directory of optional files and programs. This directory is primarily used by third-party developers to easily install and uninstall their packages.
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