Informational Commands
The following commands are used to find out some information about the user or the system.
| Linux Command | Explanation |
| ps | Lists currently running process (programs). |
| w | Show who is logged on and what they are doing. |
| id | Print your user-id and group id’s |
| df | Report filesystem disk space usage (“Disk Free” is how I remember it) |
| du | Disk Usage in a particular directory. “du -s” provides a summary for the current directory. |
| top | Displays CPU processes in a full-screen GUI. A great way to see the activity on your computer in real-time. Type “Q” to quit. |
| free | Displays amount of free and used memory in the system. |
| cat | /proc/cpuinfo Displays information about your CPU. |
| cat /proc/meminfo | Display lots of information about current memory usage. |
| uname -a | Prints system information to the screen (kernel version, machine type, etc.) |