The distinctions between science, engineering and technology are not always clear. Generally, science is the reasoned investigation or study of nature, aimed at discovering enduring relationships (principles) among elements of the (phenomenal) world. It generally employs formal techniques, i.e., some set of established rules of procedure, such as the scientific method. Engineering is the use of scientific principles to achieve a planned result. However, technology broadly involves the use and application of knowledge (e.g., scientific, engineering, mathematical, language, and historical), both formally and informally, to achieve some "practical" result (Roussel, et al.).
For example, science might study the flow of electrons in electrical conductors. This knowledge may then be used by engineers to create artifacts, such as semiconductors, computers, and other forms of advanced technology. In this sense, scientists and engineers may both be considered technologists, but scientists generally less so.
The use of technology has a great many effects; these may be separated into intended effects and unintended effects. Unintended effects are usually also unanticipated, and often unknown before the arrival of a new technology. Nevertheless, they are often as important as the intended effect.
The most subtle side effects of technology are often sociological. They are subtle because the side effects may go unnoticed unless carefully observed and studied. These may involve gradually occurring changes in the behavior of individuals, groups, institutions, and even entire societies.