How to determine hardware?

You can easily find this most of this information out with the dmidecode command:

sudo dmidecode -q

It may be a little verbose though. To find out information about a specific device, you can use the -t type argument. More information on that is here, http://www.thegeekstuff.com/2008/11/how-to-get-hardware-information-on-linux-using-dmidecode-command/

Another option would be to use lshw

sudo lshw

To find out the disk usage of your hard drive, you can use the df command:

sudo df -h

This command will tell you about your hardware (including the specific components you've listed):

sudo lshw

It's possible to run lshw without sudo (i.e., not as root) but it may not give as complete or accurate information.

You can run lshw with the -C flag and an argument, to get information about a specific class of hardware. See man lshw for details.