Working hours are the time in which a worker is obliged to perform his/her duties, that is, in which he/she is ready to perform his/her duties according to the employer's instructions, in a place where his/her work is performed or in another place designated by the employer. Full-time working hours of workers cannot exceed forty hours a week, while part-time working hours of workers are each shorter than full-time working hours. When concluding a contract of employment, a probationary period may be contracted, and the probationary period must not exceed six months. Dissatisfaction of the probationary workers is a particularly justified reason for termination of the employment contract.