Linux File System ….

/bin : holds all routine commands

/sbin: hold all files related to superuser commands

/usr : holds all files related to software packages

/lib : holds all library files required for running different software packages

/opt : holds all files related to specialized packages installed by user

/var : holds all log files related to different tasks done by linux

/tmp : holds all temporary files created by different programs

/etc : holds all configuration files required for configuring different softwares.