There are various conditions that can cause muscle twitching. Minor muscle twitching is usually the result of less serious, lifestyle-related causes. More severe muscle twitching, however, is often the result of a serious condition.
An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air).
Inert electrode: An electrode that serves only as a source or sink for electrons without playing a chemical role in the electrode reaction. Noble metals, mercury, and carbon are typically used as inert electrodes. See for example the redox electrode. The inert nature of the electrode can sometimes be questioned.