This type of internship targets recent graduates (up to 12 months from graduation). It can last between 3 and 6 months and comes with some form of financial support from the hosting company/institution (the exact amount varies from region to region).
Through an internship contract of this kind, graduates are given the opportunity to gain practical experience of the world of work, and may share their skills and knowledge with the company.
This type of internship often follows the extra-curricular internship that some students carry out as part of projects connected with their final dissertations.
More detailed information as well as details on opportunities for this type of internship (both in Italy and abroad) can be found here (Italian only).