In Linux every single file is associated with timestamps, and every file stores the information of last access time, last modification time and last change time. So, whenever we create new file, access or modify an existing file, the timestamps of that file automatically updated.

In this article we will cover some useful practical examples of Linux touch command. The touch command is a standard program for Unix/Linux operating systems, that is used to create, change and modify timestamps of a file. Before heading up for touch command examples, please check out the following options.

Full article here:
8 Pratical Examples of Linux “Touch” Command (Tecmint)