•A single processor can appear to do more than one task simultaneously by scheduling processor time

Multi-user, multi-tasking system

•Some systems use a very powerful computer called a mainframe

•These might be seen in universities or large businesses

•Lots of users with their own terminals access the mainframe’s CPU and each gets a time slice

•Each terminal is also running multiple processes

Complete Worksheet 2

Plenary

• Distributed across multiple computers
• Embedded into systems such as home appliances
• Multi-tasking, for doing several things at once
• Multi-user, to allow a mainframe’s CPU to be shared
• Real-time, to respond quickly when safety is critical
• The BIOS loads the operating system at boot time
• Device drivers allow the OS to control hardware
• Virtual machines are software emulating hardware