What is the common name for the Union Flag?

Okay, let's talk about the Union Flag, or as it's more commonly known, the Union Jack. The flag itself is a combination of three older flags representing England, Scotland, and Northern Ireland. You've got the red cross of St. George for England, the white saltire of St. Andrew for Scotland, and the red saltire of St. Patrick for Ireland. These were combined over time as the countries united under one crown. Now, here's where the "Jack" part comes in. Historically, a "jack" was a small flag flown on ships, specifically at the bow. So, the Union Flag, when flown on a ship, was called the Union Jack. Over time, the term "Union Jack" became a popular, informal name for the flag, regardless of whether it's on a ship or not. While "Union Flag" is the official name, "Union Jack" is so widely used and understood that it's considered a perfectly acceptable common name. It's one of those quirks of language and history that sticks around!