Monitoring your system basics
 
To check the disk usage on your system
~# df -h

To check the memory allocation and usage
~# free -m

To visualize your CPU information
~# cat /proc/cpuinfo

To check your network configuration
~# ifconfig

To visualize the running processes, CPU Load and Memory
~# ps aux

To see lifetime running processes
~# top
( type q to leave the program )