Which of the following is a program that uses a variety of different approaches to identify and eliminate spam?

An online discussion group that allows direct "live" communication is known as

Where are you likely to find an embedded operating system? 

................ devices convert human-understandable data and programmes into a form that the computer can process.

The software that is used to create text-based documents are referred to as 

Which of the following refers to too much electricity and may cause a voltage surge?