Intaglio is like making a picture using a special kind of printing. You start with a flat piece of metal, and then you use sharp tools and chemicals to carve your picture into it.
Once you have your picture all carved into the metal, you cover it with ink. But you still can't see the picture yet! That's because the ink is stuck inside all the little lines and grooves you carved. To get the ink out and onto paper, you have to use a special press.
The press is like a giant sandwich maker. You put the inked metal plate on one side, and a blank piece of paper on the other. Then you put the whole thing inside the press and squish it really hard.
When you take everything out, you'll have a nice, shiny picture on the paper! And because it was made using intaglio, the picture will have really cool texture and depth to it. You can even feel the grooves where the ink was pushed into the paper.
So intaglio is like a way to create special, textured pictures using a metal plate and a press.