On the same time?
You can run multiple scripts on the same PC but not simultaneously.
Multiple workflows can be run on a Machine at the same time by diferent robots, if the robots are using different Windows sessions.
Eg. You have a Windows Server 2012, and you have 3 user accounts on that machine: user1, user2, user3. All users can execute a process(the same or different) simultaniously.
The limitation is per Windows session. 1 process/1 robot/1 session
@badita coorect me ..if i am wrong here..!!