There are three levels to the forum
Guest - where you can see a few boards, mainly the board that details the activities of the society.
Member - this gives you access to other boards, such as how to get started and an area where you can seek assistance from other members. This is free to join and can be joined by anyone. However if you do not access the forum for more than 6 months then your membership will be removed. In addition access to private messages and attachments is restricted.
Full CFHS Member - This gives full access to the whole forum and is available to current members of the society. In addition to the basic boards that members have access to there are boards that cover more research in detail, transcriptions of old newsletters and from February 2013 the new newsletter will be available as soon as it is printed.
Full CFHS Members are also allowed to attach documents and pictures to posts and have the private message system to contact other members available to them. Full Members are never removed whether they use the Forum or not provided they remain members of the society.