Martin Firrell is a person who likes to create art that makes people think and feel different things. He makes art in different ways, like through words or pictures or videos.
Imagine you are reading a book and you come across a word that you don't know. You might stop and ask your mom or dad what the word means. Martin Firrell does something kind of like that. He takes a word, like "love" for example, and he puts it on a big billboard for everyone to see. People might have different ideas about what love means, so seeing it on a big sign might make them think about it more.
Sometimes Martin Firrell puts his art in places where you wouldn't usually expect it, like on the side of a building or in a park. He wants people to notice his art and think about it, even when they are doing something else like walking to school or playing in the park.
His art can be really colorful and bright, or it might be just words on a plain background. But no matter what it looks like, Martin Firrell wants you to see it and think about the big ideas behind it.