If you open several tables and then close them with the red X button you can quickly recall them through the menu system or F2 and F3 buttons. Pressing several times on the F2 button for the Browser window, or F3 button for the Map window, will produce multiple windows of the table. If there are multiple tables open in the work session a dialogue box will appear enabling you can to choose which table/s to display. This shows that the table/s have not been closed by MapInfo but are merely not being displayed in your current work space session.
MapInfo has this special facility of enabling you to open multiple windows for both your map and browser information. This aspect of MapInfo software is very powerful. If used correctly this functionality can help you to manage your mapping tasks with considerable flexibility. Just remember that if you wish to start a new project, with new map and browser layers, always use the File menu system to properly close the table/s in your current work space session.