Show Free and Used Memory in Linux

The free comman can be used to show the free and used memory on both RAM and Swap files.

Sample Usage

List Free and Used Memory in Either Kilobytes, Megabytes or Gigabytes

Kilobytes

free -k
# or
free -kilo

Megabytes

free -m
#
free --mega

Gigabytes

free -g
# or
free --giga

Show List in Human Readable Format

free -h
# or
free --human