Introduction
Often it is necessary to get the OS version, hardware statistics, running process, and details about the file system. You may need to monitor CPU percent level or check the remaining space on a hard drive. In any case, you can use the below commands.
What is OS Linux version
lsb_release -a

Get the installed memory (RAM)
free -h

Get a CPU count
lscpu | grep 'CPU(s)'

Get the hard drive details
df -h

Get disk space usage by directory
disk space used by the specified files and for each subdirectory.
du -chsk /*

Monitor Processes using TOP
Just run the command ‘top’ or ‘htop’ , if it is installed, to get real time Mem and CPU usage and see what process are resource hogs.
