The Europlug, also known as the CEE 7/16 Alternative II plug or C5 plug, is a flat, two-pole, round-pin domestic AC power plug rated for voltages up to 250 V and currents up to 2.5 A. It is a compromise design intended to connect low-power Class II appliances. The Europlug design appeared first in 1963 as Alternative II of Standard Sheet XVI in the second edition of CEE Publication 7 by the contributing members of Austria, Belgium, Czechoslovakia, Denmark, Federal Republic of Germany, Finland, France, Greece, Hungary, Italy, Netherlands, Norway, Poland, Portugal, Sweden, Switzerland, United Kingdom, and Yugoslavia. The Europlug is unusual as the standard specifies only a plug; there is no socket-outlet designed specifically for use with it.

In general, there are currently 15 types of domestic electrical outlet plugs in use worldwide, each of which has been assigned a letter by the US Department of Commerce International Trade Administration, starting with A and moving through the alphabet. The Europlug is the most common socket in Europe and is used mainly in Spain and in most countries in Europe.

In summary, the Europlug is a specific type of plug used in Europe, which is a flat, two-pole, round-pin domestic AC power plug rated for voltages up to 250 V and currents up to 2.5 A. It is the most common socket in Europe and is used mainly in Spain and in most countries in Europe.