DOS                          *nix
copy                           cp
move                           mv
ren*                           mv*
edit                           emacs, vi
format                         mkdosfs
fdisk                          fdisk
attrib                         chmod
del                            rm
dir                            ls
cd                             cd
command                        sh, bash, ksh
type                           cat
cls                            clear
more                           more, less


More coming soon....

* To do ren with mv you have to actually move the file, but you can move the file with a different name.