disk usage via command df

I'm pretty sure all of us have bunch of collections files like documents, audio and video in our computer and what is the simple way to check if the disk space usage is exceed the capacity that physical disk provided? For starter, I'm using a command called df, it cames from the package coreutils if you are using Fedora.

What is df?
df displays the amount of disk space available on the file system containing each file name argument.

Example of usage of df?

$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/vg_super-lv_root
                      51606140   9213992  39770708  19% /
tmpfs                  1977424      2348   1975076   1% /dev/shm
/dev/sda5               495844     68681    401563  15% /boot
/dev/mapper/vg_super-lv_home
                      92792824  60272440  27806708  69% /home


$ df /usr/share/man/man1/df.1.gz
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/vg_super-lv_root
                      51606140   9214012  39770688  19% /

df in techical
- Disk space is shown in 1K blocks by default, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
- if the partition is not mounted, it will not shown in the df report.


Based on the example usage shown above, the output shown is not human readable, we have to add additional parameters to the command df to make the report much more readable, I summarize some of the parameters with description which I frequently used but if you want a full list, man df to get an all parameters available to command df.

-h, with this parameter, it output human readable size, such as KiB, MiB

-H, with this parameter, it output human readable size too but use power of 1000 not 1024. You could probably noticed that the hard disk normally use this unit to measure its capacity.

-T, with this parameter, it show additional column called type to shown the type of filesystem it is formatted.

--total, with this parameter, it give you a grand total of all the mounted filesystem in the report.