The reader of this proceedings volume might ask why was it thought interesting to publish a few pages about the posters presented at IAU Colloquium 162? It had been decided that indeed the history of the meeting would not have been complete without some words about the poster presentations. The final success of the entire Colloquium depended on all presentations, either oral or poster.

The posters themselves have been different but it has been interesting to note that sometimes similar projects and ideas have been elaborated at very distant places in the world.

The basis of our teaching should be related to our roots; we ought to mention old traditions in our own country, such as the cosmological ideas of old Guarani Indians or the story of the first South American 18th century. Observatory of F. Buenaventura Suarez which have been shown by A. E. Troche Boggino of the University of Asuncion, Paraguay. However, I found most interesting the history of evolution of the human mind as depicted by the diagram of A. E. Troche Boggino showing chronological sequences of contemporary scientists, philosophers, writers, painters, sculptors and composers, from the times of Copernicus to the present day. It is easy to make a perpendicular cut or cross-section of the diagram at a given epoch, for instance that of Copernicus, and get to know what other famous persons have been living during his life-time.

In another part of the world, at the University of Glamorgan, UK, Mark Brake had been also in favour of a historical/cultural approach when telling his audience scientific facts, both when dealing with university students and with the general public.