quota

A disk quota is a limit set by a system administrator that restricts certain aspects of file system usage on modern operating systems. "Wikipedia"

Requirements : Quota Package

Where to get it : Quota package is generally available in majority of Linux Distros but still if your distro doesn't provide you with Quota compile it from http://sourceforge.net/projects/linuxquota/ :)

Step 1) Installation :

a) openSUSE : yast -i quota

b) Ubuntu : sudo apt-get install quota

c) Fedora : yum install quota

d) Others : Use rpm or compile if not available

Step 2) Enable Disk Quota

Disk quota is generally applied on a user or a set of users to its recommended to enable Disk Quota on your Home partition dont enable quota on the root partition unless you are under the expert category