Forum Home - Last Post
So starting with the Forum Home, this is the general overview of all the forums on your favourite forum, say here. If you click on a thread link from this page you'll be taken to the very last post in the thread, this allows you to quickly and easily read the last post then scroll back to last unread post in the thread before continuing to read as you normally would.
Node View - Skip to First - Skip to Last
These two controls allow you to either skip to the first post or skip to the last post in the thread. To skip to the last post then click the last post date/time stamp on the very right. If you would like to read from the start of the thread then you should click the thread start date/time stamp on the very right.
Note: You should only click the thread date/time stamp to go to the first post if you have not read the entire thread yet, doing otherwise would make one of the following behaviours redundant.
Node View - Unread Posts - Go to First Unread
This is very logical - If you haven't read the thread before then you're taken to the first post or if new posts have been made since you've last read the thread then you're taken to the first unread post.
Node View - Read Thread - Go to First Post
So you've already read the entire thread and you want to read it again from the beginning then you should click this thread link. This is the redundant control mentioned earlier.
Here is a table of options.