Parent and child
A parent and child may refer to any of the following:
1. In general, a parent is a father or mother to a child.
2. With a directory, a parent directory is a directory containing the current directory. For example, in the below MS-DOS path, the "Windows" directory is the parent directory of the "System32" directory and C:\ is the root directory.
In all command lines, you can use the cd command followed by two periods to move back to the parent directory. For example, in the above example if you were in the C:\Windows\System32 directory and typed "cd .." it would move back to the C:\Windows directory.
A parent folder and child folder are synonymous with a parent directory and a child directory.
3. When referring to a computer processes, a child is a sub process of the main parent process. It is common for the parent process to remain active or open until the child process is completed.