The word Forum is Latin, meaning Open or Public Space. It is not a derivative of a Latin word, Forum was the actual word that the Ancient Romans would have used in their speech. Aside from using it as a general gathering for a marketplace, the forum in ancient Roman times was the general cultural center.
The Forum Romanum, or Roman Forum for those who did not go to Catholic school, was a huge rectangular plaza, surrounded by very important government buildings. It is where they held triumphal processions and their elections. Public speeches were made there, criminal trials, and even gladiatorial matches took place in the Forum.
And even today, when you think about it, you can do pretty much all of those things on a forum too. Within reason, of course. The forum today is an internet chat board where people go to hold discussions about a specific subject. If you can imagine it, there is probably a forum out there for it, so the limit is whether you can find it or not.
Forums are different from chat rooms in the sense that, once a chat room is closed and done, it disappears into the ether of the internet. Whereas a forum conversation is not an instant back and forth. Instead one person posts and then waits for a response. That could be anywhere between a few minutes to a few days. Once a response is up, the original poster can go back and respond. It is a much more drawn out process, but allows for many people to partake, and to bring a certain knowledge with them.
There are a variety of ways to find a forum. You can simply search for the specific topic that you are interested in discussing, such as Kimchi Discussion Forums Free. Or, if you are just looking for a forum, with no set subject in mind, you can simply search for Free Discussion Forums.
This search will bring up a forum directory or two that you can sift through to find a chat room that sparks your interest. The forum directory will never be just a random assortment of topics thrown together on a page, it will be broken down into topics, ranging in broad to specific. For example, you could start in the forum directory Food section, then go into Meat, then choose Fish, work your way into Raw, then finally choose Sashimi. Or you can simply choose according to forum rating. You can see ratings based on things like how kid friendly they are, how user friendly it is, and how much prior knowledge you may want before venturing into a conversation on there.
The beauty with a forum is that, even though you may need to create an account to view the boards, you never need to participate if you do not feel comfortable or ready. You can sit back and watch it all, and only hop in when you feel the need to comment.