Internship is a part of university education and the first step towards professional life. The students who do internship and work part-time during their university education will not only graduate with work experience but also have met new people for reference, which is a key to professional life.
Since a company/person is connected in business with other companies/persons, a person met during internship is a key to employment in not only the company of internship but also other companies.
In multinational companies, an internship application is nothing less than a job application. In employment by a company, its interns gain an advantage over other applicants.
On the other hand, small and medium sized enterprises get considerable efficiency by employing and training qualified university students.
Internship also helps students become familiar with business life and shape their future.
Business life is much more easy for the students who lead their university life being aware of all these points.