Yet another unofficial help page!
Note: This entry refers to the old DNA (Ripley) system, not Barlesque or Pliny. The structure of URLs on the new h2g2 is different.
A companion entry to A23908151.
Let's first sort out some terminology, or this will get complicated. (It'll get complicated anyway, I know.)
Forum: A collection of conversations, stored in one area of the site. Examples: h2g2 - Ask the h2g2 Community, Today Message Board - Today's Debate, Religion & Ethics Message Board - The Moral Maze, DNA Hub - Current List of DNA Communities and Messageboards, h2g2 - The Forum, h2g2 - SEx - Science Explained Forum.
Thread:Thread is often used interchangeably with conversation, and indeed in the URLs, thread appears where we may reasonably have expected conversation to appear. Technically, though, a thread appears within a conversation, and is formed by a series of posts, each one of which is a reply to the last in the series. This needs further explanation, and I'll get onto it later. The word thread won't appear in the main section of this article.
Now that's sorted out, let's talk about finding our way around fora.
Each forum has a unique number, beginning with F. These numbers are unique across all DNA subsites, so a link from anywhere on the DNA system will be valid. /dna/h2g2/F2124165, /dna/hub/F2124165, and /dna/mbsn/F2124165 all point to the same place, the h2g2 Science Explained Forum.
As a general rule, one forum is associated with one article. Some h2g2 articles exist mainly as holding places for the attached fora (this is true, for example, of Ask h2g2, The Forum, and Science Explained), while others exist as articles in their own right (this is true of most Edited Guide Entries).
Technologically, one forum can be associated with a number of articles. This doesn't happen very often, and it may be confusing when you come across it.
Links to conversations usually include the forum number. They take the form F###?thread=###.
Each conversation has a unique number. This means that the forum specified doesn't actually matter. For example F47996?thread=3299908 and F33004?thread=3299908 bring up identical content. So too does the simpler T3299908.
Conversations may get very long. To show all of them on one page would put a ridiculous strain on the servers. So how do we declare which bits of a conversation is shown? There are two main ways and two subsidary ways:
The commands skip=X&show=Y where X and Y are numbers can be added to the URL in either order. By default, show is set to 20 and skip to 0. If you navigate through a conversation using the "next list" and "previous list" options at the bottom of the page, the skip and show commands will be used. You can also type in your own numbers, to show more or fewer posts on a page. The "next" and "previous" commands will work just as well with your new setting for "show". (Note that if the skip number is not a multiple of the show number, there may be some overlap on the next or previous list. See an example at F19585?thread=100569&skip=1&show=2, where the previous list is posts 1 & 2 and the next list is posts 2 & 3.)1
Each posting on the DNA subsites has two numbers: its location in the conversation (this number is displayed on the post itself) and its unique ID. This number is used to define what post you're replying to, in a link such as AddThread?inreplyto=47866607. In a link like T4005961?post=47026634, the unique post ID controls what part of the conversation will be displayed (in this case, posts 21-40). Of course, there are 20 different numbers, one for every post on that page, which will call up the same information.
The post command can be used in conjunction with the show command. This never happens naturally: you'll have to type it into your browser. T4005961?post=47057261&show=3. In this case, the conversation is divided up into three-post sections, and the one containing the desired post (number 32 in this conversation) is displayed. That's posts 31-33.
If you enter under the post command the ID of a post which does not occur in that conversation, you are returned the first page of the conversation whose number you entered, not the page containing the post whose ID you entered. Thus, the only way I know to retrieve a known post ID is to use the reply form: AddThread?InReplyTo=###, and then to select "Return to the conversation without saying anything". This will work only if you are signed in.
As mentioned above, the skip is by default set to zero, and show is by default set to twenty. If you're happy to see the first twenty posts in a conversation, you need not specify any extra commands in the URL at all.
To show the last page of a conversation, add &latest=1 to the end of the URL. This doesn't show the last twenty posts. Rather, it shows the last page, given that there are twenty posts to a page. Note that this form of link is unstable: as the conversation moves on, different pages will be called up by the latest=1 command.
(Note: On some DNA communities, the fora display the first post in each conversation, not just the conversation titles, as on h2g2 and the DNA Hub.)
As you're reading a conversation, how can you tell who's talking to whom? That depends on which skin you're using. In the Plain skin, there is a little note on the top of each post reading "This is a reply to this posting". The phrase this posting is a link to the post to which the post you're reading is a reply. The same phrasing appears on all the DNA messageboards and on the DNA Hub. (On the messageboards, though, it appears at the bottom of each message.)
The same appears on h2g2's Classic and Alabaster skins, but not the Brunel skin. In Brunel, there is only the 'tree icon' in the bottom right corner of each posting. This actually gives more functionality, but it's less intuitive. This 'tree icon' is also available in the Classic and Alabaster skins, but only to logged in Researchers, who can set "Expert Mode" in their Preferences.
The tree icon has five dots. The centre dot, in red, represents the current posting. This is not a link. A line drops down to the lowest dot, representing ..... I need to fill this in, and also add a bit about bookmarking conversations.
If you look at a long and complex conversation, such as the infamous "God" conversation, you will see that it starts off as a simple single thread. Post 2 is a reply to post 1, as it must be. Post 3 is a reply to post 2. Post 4 is a reply to post 3. And on until we get to post 8, which, like post 7, is a reply to post 6. Now there are two threads. The threads multiply from there. There are probably many hundreds of threads in that conversation. The situation is complicated by classic "post 21" errors, where newcomers think that post 20 is the last in the conversation and reply to it, only to land with a post number of over 2000 in what has become a totally different conversation. It is complicated also by some people's habit of simply hitting the reply button on the last post in the conversation, instead of on the post to which they are actually replying.