An adaptor allows for the insertion of one kind of plug into a different kind of socket. Even though a travel adaptor allows for the use electrical appliances abroad, keep in mind that the appliances, such as an electric shaver, may not work as well as it does at home. An adaptor does not change the voltage and frequency that is passing through cables and cords. If you are travelling with small electrical appliances and you don’t mind travelling with batteries, this may be the more hassle-free option. Otherwise, there are universal travel adaptors available for purchase.
It is possible to convert voltage, but not frequency. However some electrical appliances manufactured can handle the differences. Always check the label on your appliance.
If you’re travelling from the United States to a good portion of the world, except northern South America and Canada for example, you need a converter to step up from 110V to 230V. People who travel to the United States may need a transformer to step down from a high voltage to the lower US voltage.
Laptops today are designed with power supplies that can be used in most of the world. When travelling with your laptop, all that you may need is a plug adaptor. This also applies to digital cameras.