It is relatively easy to use most laptops abroad because their AC adapters are usually dual-voltage. If your adapter is dual-voltage (and, of course, double-check that it is), you'll need only the following to safely use your laptop outside North America:
1. A 220-volt surge protector
2. (in countries with 220-volt electricity); and An adapter plug to enable the surge protector (or AC adapter) to be plugged into the electrical outlet of the foreign country.
Note - If you will be using "dial-up" to connect to the Internet, you will also need the following:
1. A modem adapter, so you can plug your modem into a telephone jack in a foreign country; and
2. A phone-line-tester to determine whether the phone system is digital or analog (only analog is safe for your modem).