Step 6: Tang
The tang is the piece of metal attached to the blade that runs inside the handle. The top tang is a a hidden partial tang or push tang. This may be useful if there is a hollow handle with a survival kit in it (a feature I would STRONGLY recommend you do not have, due to the loss of strength). The middle blade has a hidden rat's tail or stick tang. It extends the length of the handle and the handle is pressed or threaded on to it. The bottom blade has a full tang, which conforms to the shape of the handle.
Having a partial tang may not be a sign of weakness, because it all depends on craftsmanship, but I would recommend getting a knife with a full tang or rat's tail tang. This means that even if your handle breaks, you have something to wrap a cloth around or use instead.