Electrostatic discharge (ESD) refers to the sudden transfer (discharge) of static charge between objects at different electrostatic potentials. ESD belongs to a family of electrical problems known as electrical overstress (EOS). ESD poses a serious threat to electronic devices, such as microcircuits, transistors, and diodes, and affects the operation of the systems that contain those devices. Most electronic companies regard all semiconductor devices as ESD sensitive because of the damage ESD can cause. For this reason, ESD is a major concern in the microelectronic and electronic industry in manufacture and testing. ESD concerns also exist in nonelectronic components such as disk drives, magnetic recording heads, and sensors. The article describes the causes of ESD, its damaging effects and how the effects can be prevented or minimized.