Art is a diverse range of human activities in creating visual, auditory or performing artifacts (artworks), expressing the author's imaginative or technical skill, intended to be appreciated for their beauty or emotional power. In their most general form these activities include the production of works of art, the criticism of art, the study of the history of art, and the aesthetic dissemination of art.
History (from Greek ἱστορία, historia, meaning "inquiry, knowledge acquired by investigation") is the study of the past as it is described in written documents. Events occurring before written record are considered prehistory. It is an umbrella term that relates to past events as well as the memory, discovery, collection, organization, presentation, and interpretation of information about these events. Scholars who write about history are called historians.
Lithium-ion (Li-ion) batteries have revolutionised portable consumer electronics from cameras to cell phones to laptops. Validated safety testing of larger, higher-energy installations has paved the way to large-scale stationary applications as well.