Bannock is just a unleavened (no yeast) flat bread made from wheat, barley, oatmeal or Rye flour etc. There are many forms from fruit Scones to potato soda breads etc.

https://en.wikipedia.org/wiki/Flatbread

Here is a recipe for Soda Bread (virtually the same as Bannock), which is easy to prepare and bake. Useful in a emergency situation of field cooking where preparing yeast and proofing leavened breads might difficult or time consuming.

http://www.rivercottage.net/recipes/classic-soda-bread/

How to prepare Bannock

http://www.youtube.com/watch?v=e2BU0be8f3s

Much more tasty and healthier than the stuff found in MREs and FSRs with the plasticizer chemical Azodicarbonamide found in those Bridgford Bread Sandwiches ect and even in Subway Bread

http://www.campingsurvival.com/brretoeatflb1.html