When you click on an individuals name, it will take you to his 'Profile'. Underneath that name, you'll see a tab which will allow you to 'Add Person Mark'. You can then keep tabs on that individuals as he/she will appear under the 'Favorite' tab in the header. You will then see 'Boards', 'Members', etc. All individuals and boards you mark will be there. So if you are gone for hours or days at a time, you can go to those tabs and view all the posts you missed while you were gone.