Orientation is the process of bringing employees up to speed on organisational policies, job roles and responsibilities and other organisational attributes and concepts that will help them transition efficiently into the position. In larger companies, and for roles with greater responsibilities, the orientation process may include time spent in several departments as well as specialist learning programs.
Most often people between orientation and on-boarding, while on-boarding includes the orientation element, it encompasses much more. Though a typical orientation may stretch over several days it is a one time event while on-boarding is an ongoing process which can go up from several months to years.
Orientation usually takes place in a classroom setting with one way flow of information while on-boarding is a two way exchange of information and may take several sessions.