The first link in Britain's armor: radar. Chain home was not just a radar system, but an integrated data processing network, that allowed Britain to make the most of its limited resources during the Battle of Britain.
The Dowding System does not have the iconic status of the Spitfire, but like the Spitfire, took a pivotal role in the success of the Battle of Britain. This is how it worked.
The Battle of Britain was a battle of attrition. No territory was traded during the 3 month campaign. The winner was determined by who could maintain two vital supply chains.