Static ports are by no means unique to Concorde; all aeroplanes have them. They measure the air pressure around the aeroplane, and this value is used in various aspects of aircraft instrumentation. In particular, it is used (together with the dynamic pressure value) to display indicated air speed.
Dynamic pressure is what the pitot heads produce - those forward-pointing tubes either under the wings or (as in the case of Concorde) alongside and on the nose which simply measure the pressure of the air generated by the aircraft's forward movement through the air.
By the way - engine bay doors; we open one on OAC for our Technical Tours (not the shorter, 'Classic', tours where there wouldn't be time) so we can show the 593 Olympus and tell our visitors about it. Those doors certainly are heavy!