Most laptops available today come equipped with usb  ports, not serial ports. for these laptops,
you need a USB-to-serial connecter to access the device ,as shown in figure 1-4

Ethernet cable types

A straight-through cable or crossover cable is a type of ethernet cable used to connect computing devices together directly.

A rollover cable(also known as cisco console cable or a yost cable) is a type of cable that is often used to connect a computer terminal to a router,s console port.