Well hello there little one!
So, a really long time ago there were some people called Greeks who lived in a place called Greece. Now, these Greeks were really good at lots of things, like making cool buildings and art, and they were also really smart.
Now, some of these Greeks decided to travel to a place called Italy. Italy was a bit different from Greece - they spoke a different language and their culture was different too.
When the Greeks got to Italy, they started to build their own cities and towns, just like they did in Greece. But they also mixed with the Italian people, and together they started to create a new kind of culture.
The Greeks in Italy brought with them their knowledge of things like philosophy, science and math, and they introduced these ideas to the Italians. The Italians were very impressed and they started to learn from the Greeks.
This mix of Greek and Italian culture had a big impact on Italy. It helped to shape the art, architecture, language and even the food of Italy. Some people even say that the Greeks helped to make Italy the amazing place that it is today!
So, in summary, the Greeks were really cool people from Greece who went to Italy a long time ago. They mixed with the Italians and together they created a new kind of culture, which had a big impact on Italy.