Hewlett Packard announced the fourth basic element of the electronic circuits along with the resistor, capacitor and Inductor.
Memristors also called to be as the memory resistors are a class of passive ideal circuit elements that maintain a functional relationship between the time Integrals of current and voltage across their two terminals.
This results in resistance varying according to the device’s memristance function.
Specifically engineered memristors provide controllable resistance useful for switching current. Until the Hewlett Packard announced on April 30, 2008 that the thin films of titanium dioxide behave as nearly ideal memristors with good switching qualities.
In other cases, memristance theory is used as a mathematical model for empirically observed phenomena.
Memristors can implement memory on the principle that Direct Current applied in the component can adjust its apparent resistance.