There have been 3 versions of Simula. Soon thereafter, influenced by C.A.R. Hoare's ideas on records, the designers realised that they could do dynamic modeling with a general purpose extensible language based on Algol-60. Activation record produced by call to a class, called an instance of the class.
Classes are procedures that return objects.
The philosophy of OOPL's and the design methodology, etc. is not here. Draw intersecting circles Cp and Cq, centered around p and q. 2. Draw intersecting circles Cq' and Cr, centered around q and r. 3. Draw line L1 through the points of intersection of Cp and Cq. Draw line L2 through the points of intersection of Cq and Cr.