Culture Talk

Is it actually rude not to tip when you travel? Genuine question

Going to the US for the first time this summer. In Ireland we tip a bit if the service is good, but it's not expected the way people describe it over there.

I keep reading conflicting things. Some say it's mandatory, some say it's gotten out of hand with tip screens everywhere. What's the real situation, and what do you do when you're abroad and don't know the local rules?