Can someone please explain what each of this actually does?

Private Declare Function FindWindowA& Lib "User32" _
(ByVal lpClassName$, ByVal lpWindowName$)
Private Declare Function SetWindowLongA& Lib "User32" _
(ByVal hWnd&, ByVal nIndex&, ByVal dwNewLong&)
Private Declare Function OpenClipboard& Lib "User32" (ByVal hWnd&)
Private Declare Function EmptyClipboard& Lib "User32" ()
Private Declare Function CloseClipboard& Lib "User32" ()
Private Declare Sub keybd_event Lib "User32" (ByVal bVk As Byte _
, ByVal bScan As Byte, ByVal dwFlags&, ByVal dwExtraInfo&)

Thanks in advance