As previously said, it is an easy way to file those postings that you want to be able to locate the information for later. That way you don't have to serf thro all of the postings only those you have in the marked section.
You can also use it to click all the ones you have read...this way you don't have to search for new ones.
I give a flower for this and then I can tell very quickly if I have read it or responded to it.
You can make it easer to find the questions or answers you want to keep track of. You will see a tab that has (marked "check mark") if you click on that tab it will bring up all the ones you have checked. I bet this is as "clear as mud". Welcome to the "cutie" family. Sue *4U
When you click a question you want to remember you can easily get back to them by clicking on the check mark under the tabs. I use it I want to see the answers given to some one else's question and find it quite useful.
I mean the one in "show: All | my questions | my answers | marked ". All of them are in fact quite handy.