Translatory motion is when something moves in a straight line from one place to another. Think about a toy car zooming across the floor - that's translatory motion!
Imagine you have a toy car and you're going to push it across a table. When you push it, it moves straight across the table without turning or twisting. That's translatory motion.
Now, if you were to give the toy car a spin, like a top, that would be rotational motion - it's turning around and around. But if it just moves straight from one place to another, that's translatory.
Translatory motion can also be used to describe bigger things, like a car driving down the street or an airplane flying through the sky. As long as it's moving in a straight line without twisting or turning, it's translatory motion.