Usually, you can find some restrictions for the displayed data. Enter your restrictions and press the "Show", or "Search" button to apply it. Click on the word "Filter" or on the +/- icon to hide/show the filter.
A TIP (a useful information) concerning the page. Click on this icon to show it.
Hold the mouse pointer over this icon to see a short description/help.
A list of symbols, explanations, used abbreviations...
A message announcing an error.
An information, e.g., a successful change of data...
You can find the tabs usually above a table and they represent possible view styles and exports.
You can find this object typically on the top and at the bottom of the page in a green stripe. If this icon is present, you can click on it to display a printable version of the page (without menus, filters...).
You can use these icons to select all/none, and invert your selection in tick boxes.