ubuntu:~$ free -m
             total       used       free     shared    buffers     cached
Mem:          5952       5836        115          0        286       1806
-/+ buffers/cache:       3743       2208
Swap:            0          0          0
ubuntu:~$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda1        21G  6.3G   14G  32% /
udev            2.9G  4.0K  2.9G   1% /dev
tmpfs           1.2G  928K  1.2G   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            3.0G 1020K  3.0G   1% /run/shm
/dev/sda2       911G  460G  451G  51% /media/PENDRIVE