From my point of view, hobby plays an important role in a person`s life. Now I would like to set some examples to prove this statement.
Firstly, it helps get out of depression and raise our spirits. For instance, you have been frustrated. But if you have a favourite occupation, while passing the time you are getting involved in the process and gradually forgeting about the previous failure. As it is known, this is an exellent way of entertainment after an unsuccessful experience, as your attention is fully concentrated on the thing you are doing.
Secondly, a hobby can also help choose a career path for the future. For example, when doing sport you understand that you can not live without it and this is your natural rate. Such people usually become professional sportsmen, Trainers.
Apart from that, it refers to other spheres of activity. To conclude, hobby is not only a way of calming down and relaxing, but also it can be a useful experiment for your future job.