A portable object in computing is like a toy that you can bring with you wherever you go. Just like how you can take your favorite toy with you to a friend's house, a portable object can be taken from one computer to another.
Imagine you have a toy car that you can play with at home. But if you wanted to play with it at your friend's house, you'd have to bring it along with you. This is kind of like how a portable object works in computing. Instead of a toy car, it could be a file or a program that you want to use on a different computer.
The reason why this is important is because some programs or files may only work on certain computers or operating systems. But if you make them portable, you can take them with you and use them on any computer that supports them.
So overall, a portable object is something that you can easily move from one computer to another, just like how you can bring your favorite toy with you wherever you go.