A cathode is a type of electrode through which electrons move. Electrodes are an electrical conductor (usually a metal) that is connected to something that is not a metal. The cathode type of electrode delivers electrons (negative charge) and the anode collects electrons (has the positive charge).
In other words, a cathode is a positive electrode on a battery and a negative electrode on an electrolytic cell. Electric current is perceived as flowing in the opposite direction that the electrons are flowing. So electrons go into the + terminal of a battery, but electric current goes out. Electrons go into the - terminal of an electrolytic cell, but electric current goes out.
An electrode through which electrons flows out of the device is termed an anode because it is positively charged. An anode is a negative electrode on a battery and a positive electrode on an electrolytic cell.
Images for kids
Cold cathode (lefthand electrode) in neon lamp
Cathode Facts for Kids. Kiddle Encyclopedia.