These three icons are common across all systems settings. The first icon will open the display in a new window. The second is used to Edit a record. The third is used to Add a New Record.
Once you enter Edit mode these icons will appear, the first one will take you back to view mode. The second one will delete the record. As soon as you start editing the view icon will disappear.
Once you start editing a record these icons will appear. The first icon is the Save icon. The last one will undo any changes you have made.
In some areas there is an option to add positions. This is used to indicate where in a drop-down menu the item should sit.