Pull mode is one of the four modes in Foldit's original interface. It's the default mode for playing Foldit. The tools in this mode directly manipulate the shape of your protein. As the name suggests, pull mode lets you adjust the shape of the protein by clicking on the backbone and dragging with the mouse. You can also click on a sidechain and drag it to a new position, which doesn't change the shape of the backbone. Pull mode can be selected from the modes menu of the original interface, or by using the keyboard shortcut "1".