Okay little buddy, think of it like this: you know how when we talk about things, we use words to describe them? Well, when people talk about God and important religious ideas, they want to make sure they are using the right words and saying things in the right way.
That's where something called "theological markup language" comes in. Just like how a computer needs special code to understand different commands, people who study religion created a special code that helps them talk about God and religious stuff in a clear and organized way.
This code is called a "markup language" because it's like highlighting or underlining important parts of a text. It's a way to show that certain words or phrases are really important, or to give instructions on how things should be read or understood. Using this code helps people who study religion to communicate better with each other and understand religious texts more accurately.
So, even though it might seem confusing at first, theological markup language is basically just a special way of talking about God and religion that helps people say exactly what they mean and understand each other better. Cool, huh?