Prior to early 1970s, traditional methods were the principal means of controlling the number and spacing of births. Today, an estimated 57 per cent of the world’s married women use contraceptives and half use modern methods such as medical sterilizations. Recent statistics suggest that Canada has the highest sterilization rate in the Western world. This paper presents findings of research exami...

This paper addresses the lack of solid historical information concerning early computer game sales and preferences. Two consistent data series from the magazines Softalk and Computer Gaming World (CGW) are analyzed to give an overview of the best selling and best rated games by players for the period of 1980-1984. A “genre palette” is inferred from the sources, giving a snapshot of how contempo...

This paper investigates the desirable properties of programming language constructs that support encapsulation of environments and abstract data types. These properties are illustrated by using a simple multiuser file system as a model. The requirements for such a file system are outlined; then the model file system design is described by a hierarchy of encapsulated abstract data types and envi...