Unemployment is when a person who is of normal working age (usually about 15-18 to about 60-65) does not have a paid job. They therefore do not get paid a salary. In some parts of the world, there are social networks to care for the unemployed.
The unemployment rate is the number of unemployed people divided by the total population of that age group of a country. The unemployment rate is influenced by many things, including the government of a country to the average age of a country's population. Unemployment is a bad thing for society.
A certain amount of unemployment is natural. 'Full employment' does not mean no-one is out of work. Governments now aim to increase the number of jobs (which can be done) rather than cut out all unemployment (which cannot be done).
- Tom de Castella & Caroline McClatchey 2011. Whatever happened to full employment? BBC News magazine