When traveling to foreign countries make sure you get all the facts straight BEFORE going on your trip. This will save you money, time and unnecessary trouble.
An issue, that is easily forgotten about, is outlets and voltage.
If you are going from North America to Europe, make sure you keep the 220 volts in mind. Girls: do NOT use a hair straightener, curling iron, hair dryer,… without a converter. It will blow faster than you can curl your first curl. A simple adapter-plug wont do the trick.
As far as cellphone chargers, plugs for laptops and such go, you will usually be fine with just an adapter plug because the power supply unit of your electrical devices will do the job for you.
An easy way to check if you can go without using an actual power converter/transformer (which weighs a ton and isn’t cheap), is to just look directly on the plug.
i.e. My camera charger says “input: ca. 100V-240V 50/60Hz 4-7VA” in tiny writing on the bottom.
This set is great because you’ll be set for any country you visit.
It’ll cost you about 8-10$ and is a great investment if you travel a lot.
You can get the pictured set here.