A microkernel is a kernel containing many components that are optimized to reduce resident memory size.

Virtual machines first appeared commercially on mainframes in the 1970s.

A graphical user interface (GUI) is impractical for most mobile systems.

With containerization, we can have multiple OS in one bare metal hardware.

In the message-passing model, the communication processes exchange messages to transfer information.

A signal propagates at a speed of 300000 km/second. The distance between Jakarta and Kabul is about 6000 km. If the signal frequency is 3GHz, about 600 million cycles will be between Jakarta and Kabul.

Debugging is finding and fixing errors in a system only in software.

Constantly running system-program processes are known as services.

General-purpose operating systems that provide standard functions and Virtual Machine Manager (VMM) functions are known as Type 0 Hypervisor.

A clustered system gathers together multiple CPUs to accomplish computational work.