Traveling abroad in the '60's through 80's, I only had to worry about having extra alkaline batteries, and if my hotel had a bathroom adapter for my electric razor.
Today, my list of travel and photography gear, needing an electrical outlet to work or get charged, seems to go on forever. My travel electrical needs, like so many travelers, is significant.
Just as most every country has its own language, and currency, and definitely its own culture, countries have their own electrical power specifications. Travel photographers, like any traveler, need to be aware of the electrical milieu of the countries they're visiting, so they are prepared for their stay.