As you probably guessed, electrical standards abroad are different. The US uses 120v/60Hz. Thailand uses 220v/50Hz. That means if you plug an appliance that is set for 120v/60Hz into an outlet in Thailand, there will probably be lots of sparks and smoke, and possibly some charred flesh. I did this once in Uganda, and the resulting smoke and sparks were entertaining, if not expensive.
Now, this doesn’t mean that your US electronics won’t work abroad. Almost all modern electronics are dual- or multi-voltage, meaning it will work at 120v or 220v. Check the label on the power supply to make sure, but all of my electronics, including my MacBook Pro charger, Fujifilms digital camera battery charger, iPhone charger, GoPro charger, and my son’s Nintendo DS power adapter are multi-voltage. Typical multi-voltage label looks like these:
If it is dual voltage, it will say something like INPUT: 100v-240v, 50-60Hz or AC IN: 100v-240v, 50-60Hz.