Okay, so think of a book that has the same story written in different languages like English, French, and Spanish. Hexapla is like that but instead of different languages, it has the same story written in different versions of the same language.
For example, long, long, long ago, there was a really important book called the Bible. It was written in old languages like Hebrew and Greek. But over time, people wanted to read it in languages they could understand like Latin and English.
So, Hexapla was created to help people understand the Bible in different versions of the same old languages. Hexapla had six columns and had the Bible written in the original Hebrew, translated into Greek, and then translated again into four other versions of Greek.
It was like a really big and helpful tool for scholars and religious people who wanted to understand the Bible better.