pls help - /dev/dsk 100% full

I use the following command dk -k and get the following output:

Filesystem kbytes used avail capacity Mounted on
/dev/dsk/c0t0d0s0 1587078 56546 1482920 4% /
/dev/dsk/c0t0d0s6 1984230 926199 998505 49% /usr
/proc 0 0 0 0% /proc
fd 0 0 0 0% /dev/fd
mnttab 0 0 0 0% /etc/mnttab
/dev/dsk/c0t0d0s4 1484262 1483645 0 100% /var
swap 1434856 8 1434848 1% /var/run
swap 1434856 8 1434848 1% /tmp
/dev/dsk/c0t0d0s7 13071195 1139648 11800836 9% /home

The /dev/dsk/c0t0d0s4 says it's 100% full. How do I free up the space and or see what's take up the space? I acassionally get disk full when I try to write/edit some files. I'm new to Solaris commands with some experience with command lines. Greatly appreciate any help you can give.

Thanks in advance.

Mark

See Filesystem full at the top of the Solaris forum.