A leaf is actually a file within a directory in your hard drive . Do you know what is the similarity between a computer’s hard disk and a tree? Even though the hard disk does not look like a tree from outside, it is organized in the same way from 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 it, while the files are its leaves or leaves. So a leaf is actually a file inside a directory in your hard drive.
Technically speaking, a leaf is a node of a tree that does not contain any child nodes. Since there cannot be too many child nodes in files, like folders, they are always leafs. When we refer to a tree structure, then a leaf is called a leaf node.