The primary purpose of the condenser is to prevent arcing (burning) of the points as they open.
The coil is a "step up" transformer. The voltage and current flowing through the primary winding is induced into the secondary winding (connects to the big wire going to the distributor) producing a lot more voltage (enough to jump the gap of a spark plug) and a lot less current.
Maybe a drawing will help.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
