Which technology is used in compact disks ?

Which of the following is not an output device ?

Software, such as Explorer & Firefox referred to as ____

When a key is pressed on the keyboard, which standard is used for converting the keystroke into corresponding bits ?

Which technology is used  in the processor of a computer  to simulates a single processor into two virtual processors to the operating system? 

What is the process of loading the operating system  files into dynamic random access memory?