Linking elements
You can link the different pads of elements together so that the elements
form a chain.
By linking these three elements, we have created a very simple
chain. The effect of this will be that the output of the source element
(element1) will be used as input for the filter element (element2). The
filter element will do something with the data and send the result to
the final sink element (element3).
Imagine the above graph as a simple MPEG audio decoder. The source
element is a disk source, the filter element is the MPEG decoder and
the sink element is your audiocard. We will use this simple graph to
construct an MPEG player later in this manual.