no, it is confusing at first.
if you have a soundcard you have a midi interface built into the computer, and you buy a cable from the 15 pin D joystick port on the pc to two 5 pin DIN plugs, midi in and out. this is what you've got.
if you have no soundcard, no midi interface, if your laptop has no joystick port, you can use the 'host' computer connection if you have a 9 pin D RS232 serial port on the laptop, cable to mini p/s plug 8 pin. This will work on most existing keyboards which have a 'host' connector on the back.
if you have no joystick port and no serial port but you do have a usb port, you can buy a usb midi interface, usb to two 5 pin DIN plugs, midi in and out, but this is the most expensive solution of all.
if you buy a 7000 you need none of these, all you need is a usb A to B cable, and is the simplest, cheapest and best solution technically. Because of this the 7000 no longer has a 'host' connector because it is no longer needed, and there are a few other tricks inside to make it better for midi too.
ps there is no usb on the 6000, there is a usb on the sx6 hard disk which fits in 6000 and 6500 but is not used yet... this is a different animal though.