How to check FileSystem usage ?

df -h / df -k are the commands to check filesystem usage .

Form the below example lets take /linuxtechnotes file system  as example .

Size :- is total size of /linuxtechnotes filesystem which is 582M.
used  :-  is total usage  of /linuxtechnotes filesystem which is 11M.
Avail :-   is total size of /linuxtechnotes filesystem which is 542M.
Use% :- is total % usage  of  of /linuxtechnotes filesystem which is 2%.
mounted on is the filesystem name .