A leaf is a file within a directory in your hard drive. Do you know the similarity between a computer’s hard disk and a tree? Even though the hard disk does not look like a tree from the outside, it is organized similarly from the inside.
Directories of Files and Folders are organized in a Hard Disk as branches, whereas each directory has a branch with files and folders. Folders take the form of branches in them, while the files are their leaves or leaves. So a leaf is a file inside a directory in your hard drive.
Technically speaking, a leaf is a tree node that does not contain any child nodes. Since there cannot be too many child nodes in files, they are always leafs like folders. When we refer to a tree structure, a leaf is called a leaf node.