Micro-electro-mechanical systems (MEMS) is a term originally coined in the United States in the 1980s. In Europe the term microsystems technology (MST) is more usual, whereas in Japan the term micromachines is more widespread. These terms all refer to the same technology that is a by-product of the enormously successful semiconductor-microelectronics chip manufacturing industry. In this article the term MEMS will be deployed more generically, as it may be viewed as being a more accurate description of the science and technology underlying these miniature devices whose dimensions are measured in micrometers.