Diphtheria (dif-THEER-e-uh) is an infection of the lining of the upper respiratory tract (the nose and throat). It is a serious disease that can cause breathing difficulty and other complications, including death.
The Internet is not synonymous with World Wide Web. The Internet is a massive network of networks, a networking infrastructure. It connects millions of computers together globally, forming a network in which any computer can communicate with any other computer as long as they are both connected to the Internet.
(1) A group of related components that interact to perform a task. (2) A computer system is made up of the CPU, operating system and peripheral devices. All desktop computers, laptop computers, network servers, minicomputers and mainframes are computer systems. Most references to computer imply the computer system.. See computer system.