Df
Gives an overview of the filesystem disk space usage.
Display all filesystems and their disk usage:
df
Display all filesystems and their disk usage in human-readable form:
df -h
Display the filesystem and its disk usage containing the given file or directory:
df path/to/file_or_directory
Display statistics on the number of free inodes:
df -i
Display filesystems but exclude the specified types:
df -x squashfs -x tmpfs