Conscription is the compulsory enlistment of people in some sort of national service, most often military service.

Conscription dates back to antiquity and continues in some countries to the present day under various names.

The modern system of near-universal national conscription for young men dates to the French Revolution in the 1790s, where it became the basis of a very large and powerful military.

Most European nations later copied the system in peacetime, so that men at a certain age would serve 1–3 years on active duty, then transfer to the reserve force.

Conscription is controversial, because of conscientious objection to service, or political objection to service for a disliked government, or an unpopular war, and because it violates individual rights. Those conscripted may evade service, sometimes by leaving the country. Some selection systems accommodate these attitudes by providing alternative serviceoutside combat-operations roles or even outside the military, such as Zivildienst in Austria and Switzerland.

Source: Wikipedia