To see how much disk space you have left on your system, you need to use the "df" command, which stands for "disk free". df As you can see, "df" output is not exactly intuitive -- and we've even simplified it a bit. On a real system, the first column is actually "Filesystem", but that column is totally useless to the average user. In our example, the first three columns show the total disk size, the disk space used, and the available disk space. All of these numbers are in kilobytes. Notice that the "Used" and "Available" columns do not add up to the "1k-blocks" (total) column. That is because a percentage of the disk is always set aside for administrative use. In this case, 5% of each disk is reserved. Actually, if you just ignore the "1k-blocks" column, everything will make more sense, because it is the only one that deals with total disk space, rather than "user" disk space. Since a regular user doesn't have access to the reserved 5% of a disk anyway, you might as well pretend that it doesn't exist. The "Use%" column shows the percentage of user space that is currently used. The "Mounted on" column shows where the disks reside in your filesystem tree. This column raises enough questions to warrant a separate page of explanation. Click the right arrow.