What is the difference between an internship and a traineeship?

A traineeship is a paid job for those who recently graduated, while an internship is part of a study.

An internship (stage) is usually a mandatory part of the education that focuses on learning. It is a work
placement or practical training arrangement that allows the student to gain practical work experience in the field of one’s study in a company. Internship is typically shorter-term work (3 months to a year) experience for students. Internships are usually not paid, but can be remunerated modestly. Because an internship is a learning goal, this allowance is not regarded as a salary.
A traineeship in the Netherlands is typically a starter’s position for graduates with a normal salary. Essentially you get paid to learn. A traineeship is a paid (entry level) position in a company/ organisation for a graduate who aims to develop professional skills etc. It is a job.