Docking and Anchoring in VB are used to make sure that a control covers the whole client area of a form.
Upon "docking" a window, it adheres to the edges of it's container (the Form). To "dock" a particular control, select the Dock property of the control from the properties window.
Selecting the Dock property opens up a small window like structure where you can select towards which side on the Form should the control be docked.
You can use Anchoring to "anchor" a control to the edges of it?s container (the Form). Selecting this property in the properties window opens up a small window from where you can select what edge to "anchor" the control to.