Conscription, also called draft, is when a government forces people to join the armed forces. Usually, only men are conscripted, but in Israel, women are as well. A soldier who has been forced to serve in the army is called a conscript. Conscription is a very old way to build up armies, but also usually very unpopular, since very few men enjoy fighting and killing other people. Historically conscription was called levy, but it was so unpopular that it was used only when the country was in really dire danger.
The first true conscript army was the French Grand Army in the French Revolution. The French revolution leaders drafted all French men into the army. The result was that the French army was five times larger than that of neighbour countries, and the sheer numbers often won battles for the French. While the French soldiers were poorer trained and equipped than the soldiers of the neighbour armies, the amount of the soldiers made up for that. Conscription became the universal way of making up the armies after the French Revolution. Almost all armies in the world except United Kingdom were conscription armies. Without conscription, the large armies of World War One and World War Two would have been impossible to form.
Conscription armies are very large, but they are often very poorly equipped and trained and have poor morale. In combat they usually suffer many casualties. Usually conscripts serve with no pay and are treated little better than slaves. Conscription can be considered as a form of forced labour. Men usually do not like to fight and kill each other, and many men fear to be killed or maimed. In many countries, young men who refuse to join the army are sentenced to prison. Many people "dodged" or illegally avoided conscription during the Vietnam War in the United States.
Sometimes conscription can be justified. For example if a country is small and has too few inhabitants (= people living in the country) to attract enough volunteers, it can make up a large enough army by conscription. If a country is in the midst of hostile neighbours and war can break up at any time, or if the country is a buffer state (= is located between two military blocks), training all available young people as soldiers can be a good idea.
The alternatives for conscription are militia system, as in Switzerland, or professional army made up from volunteers. The first country to give up conscription was United States. The Vietnam War proved so unpopular that the Army no longer wanted conscripts, but volunteers, which have better motivation to serve. Most other Western World countries followed the American example and gave up conscription. All American countries now have all-volunteer army and in the Europe universal conscription remains only in Finland, Russia and Turkey.