FTP is like a magic postman that helps you send and receive files between your computer and a designated server.
Imagine that you have a toy that you want to give to your friend who lives in another house. You cannot just throw the toy over the fence, right? So, you call up the magic postman (FTP) to come and pick up the toy and deliver it safely to your friend's house.
Similarly, when you want to transfer a file from your computer to a server or from a server to your computer, you call up the magic postman (FTP) to pick up the file and deliver it to the right place.
The magic postman (FTP) always needs to have the right address and key (username and password) to access the correct server. Just like how you need to know your friend's address and where they keep their toy box to deliver the toy properly.
That's it! FTP is like a magic postman that helps you transfer files between your computer and a designated server.