A omestic worker, domestic, or servant is one who works, and often also lives, within the employer's household. They are distinguishable from serfs or slaves in that they are compensated, that is, they must receive payment (and, following labour reforms in the 20th Century, benefits) for their work. They are also free to leave their employment at any time, although foreign workers may find these freedoms restricted by, for example, visa regulations. In large households, there can be a large number of domestic workers doing different jobs, often as part of an elaborate hierarchy. However, most such employees work in middle class households, where they are the only servant.