Mary Ann,
There are several types of "data ports" on hotels in my experience.
There is an ethernet data port, a modem data port, and a wireless
internet connection.
For the ethernet data port, you just need an ethernet cable, also
called a CAT5e cable. This will connect your ethernet port on your
computer to the ethernet port in the hotel room.
The modem data ports are usually part of or near the phone. These ports
require a standard telephone cable to connect your laptop modem to the
modem data port in the hotel.
Wireless is possibly the easiest. If you have a wireless card in your
notebook, you just have to ask the staff how to connect and you should
be fine. No wires are needed.
I hope this helps.