Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Direct current
open-in-new
<p>Direct current (DC) is one-directional <a href="/facts/Electric_current/Dc1xdnUX">flow</a> of <a href="/facts/Electric_charge/xxsBfmlB">electric charge</a>. An <a href="/facts/Electrochemical_cell/o7oEnYVl">electrochemical cell</a> is a prime example of DC power. Direct current may flow through a <a href="/facts/Conductor_(material)/BSuyupLP">conductor</a> such as a wire, but can also flow through <a href="/facts/Semiconductor/zFf3mGTE">semiconductors</a>, <a href="/facts/Electrical_insulation/SfSXkrh5">insulators</a>, or even through a <a href="/facts/Vacuum/BTk3goyV">vacuum</a> as in <a href="/facts/Electron_beam/9jRXSquS">electron or ion beams</a>. The electric current flows in a constant direction, distinguishing it from <a href="/facts/Alternating_current/qxICS3xa">alternating current</a> (AC). A <a href="/facts/Archaism/fs11Vfza">term formerly used</a> for this type of current was galvanic current. </p><p>The abbreviations <i>AC</i> and <i>DC</i> are often used to mean simply <i>alternating</i> and <i>direct</i>, as when they modify <i><a href="/facts/Electric_current/Dc1xdnUX">current</a></i> or <i><a href="/facts/Voltage/EN2po6N2">voltage</a></i>. </p><p>Direct current may be converted from an alternating current supply by use of a <a href="/facts/Rectifier/me8XDxND">rectifier</a>, which contains <a href="/facts/Electronics/E4JhgISq">electronic</a> elements (usually) or electromechanical elements (historically) that allow current to flow only in one direction. Direct current may be converted into alternating current via an <a href="/facts/Inverter_(electrical)/L8cJc3Hu">inverter</a>. </p><p>Direct current has many uses, from the charging of batteries to large power supplies for electronic systems, motors, and more. Very large quantities of electrical energy provided via direct-current are used in smelting of <a href="/facts/Aluminum/7wmR8jYE">aluminum</a> and other <a href="/facts/Electrochemistry/C0RUWpBH">electrochemical</a> processes. It is also used for some <a href="/facts/Railway_electrification_system/WksMTQ4u">railways</a>, especially in <a href="/facts/Urban_area/fu9v8h5P">urban areas</a>. <a href="/facts/High-voltage_direct_current/FDIob86A">High-voltage direct current</a> is used to transmit large amounts of power from remote generation sites or to interconnect alternating current power grids. </p>