"Rostrum" is another word for dais or lectern - it's something people stand at to speak. While Rostrum certainly helps people speak in formal situations where such devices are used, the skills learnt can be used in a much wider range of situations as well.

The public speaking club of that name was founded near Manchester in July 1923 by Sidney Wicks. Australian Rostrum was founded in 1930 in Sydney, spreading to Victoria in 1934. For the past 80 years, Rostrum has been helping people improve their public speaking skills.