The -h flag for commandline commands

Interestingly enough, most Unix users fail to use the -h flag.
This is because it was written into POSIX versions of the same commands and thus only worked for linux until just recently (unless you installed it yourself). Later versions of Solaris and other Unixes may have this supported. So what does the -h flag do?
It makes things human readable. So basically if you do this at the commandline:
df
You are probably used to seeing something like this:

Filesystem 512-blocks Used Avail Capacity Mounted on
/dev/disk0s2 390050144 298010904 91527240 77% /

but with the df -h command, you would see something like this:

Filesystem Size Used Avail Capacity Mounted on
/dev/disk0s2 186G 142G 44G 77% /

Notice that the readings are not in 512 blocks anymore, and has designations of how many GIGs of space or whatever your space is designated by. This is human-readable content. Useful when you don’t feel like counting the number of digits across to figure out if you’re in the gigabyte or terabyte range.