Early computers had only one processor. Therefore, there was never any real
concurrency in the computer. The only concurrency was apparent concurrency
created by the operating system as it shared the processor among several distinct
tasks or processes. Modern computers are likely to have many processors. These
may be truly distinct processors all part of the one computer. However even a
single processor may be able to run more than one process at a time by having
multiple cores. The Intel Core Duo processor is a well-known example of such a
multicore processor.