Which command is used to create an empty file in Linux?

The command that is used to create an empty file in Linux is touch. This command is specifically designed to change the timestamps of a file, but if the specified file does not exist, it will create an empty file with that name. This is a commonly used method for creating files in scripts or when you want an empty file as a placeholder.

In contrast, the mkdir command is used for creating directories rather than files, making it inappropriate for the task of creating an empty file. The cp command, which is utilized for copying files and directories, does not create new empty files unless it is copying from an existing file. Lastly, the rm command is intended for removing files or directories, not for creating them. Therefore, touch is the correct and straightforward choice for creating an empty file in a Linux environment.