Ferroelectricity is a property of certain materials that exhibit a spontaneous electric polarization, meaning they can maintain an electric charge even without an external electric field. This polarization can be reversed by applying an external electric field, allowing these materials to switch their charge orientation. Common examples of ferroelectric materials include barium titanate and lead zirconate titanate. These materials are used in various applications, such as capacitors, sensors, and memory devices, due to their ability to store and manipulate electrical energy efficiently.