What is the meaning of a "system user" term in Plesk? What is it stands for?
For each hosting subscription, Plesk creates a System User - a user account in the Plesk server operating system. Customers obtain their system users' access credentials from their service providers and use these credentials for connecting to the server through FTP, SSH, and so on. In addition, all operations with files and directories in Plesk are performed on behalf of system users. For example, when a customer adds a new file in File Manager, the subscription's system user becomes the owner of the file.