Yes, if they are in the correct department, or the ticket is assigned to their account, they will receive an email notifying them of a new ticket.
By "forwarded" email, this means that the person who receives the email about a new ticket creation would Forward that email to the persons email address that needs to know about the ticket, which isn't automatic.
I'd recommend setting everyone up with accounts in OST regardless of whether you ever intend on assigning a ticket to them or not. It's just easier this way and they can login at their leisure but still know about the problem.