gives the login name of the user who invoked the Wolfram Language kernel, as recorded by the operating system.
- On Unix and similar operating systems, $Username is derived from the UID associated with the Wolfram Language kernel process.
- On operating systems where no login name can be found, $Username is None.
- For compatibility with code written prior to Version 12 of the Wolfram Language, the value of $Username is also stored in the variable $UserName.
Introduced in 1996Updated in 2019