Scala is a scalable object-oriented programming language with features found in functional programming languages. Nowadays, the object-oriented approach to software construction is considered the most succesful methodology for software design, mainly because it makes software reuse extremely easy. On the other hand, functional programming offers some very elegant tools which when combined with an object-oriented program development philosophy define a really powerful programming methodology. Generally, any programming language that can be extended seamlessly is called scalable. When all these ideas are combined in a single tool, then the result is a particularly powerful programming language.

Object orientation

The first object-oriented programming language was SIMULA, which was designed and implemented by Ole-Johan Dahl and Kristen Nygaard. The SIMUlation LAnguage was designed “to facilitate formal description of the layout and rules of operation of systems with discrete events (changes of state).” In other words, SIMULA was designed as a simulation tool of discrete systems. Roughly, a simulation involves the representation of the functioning of one system or process by means of the functioning of another. In order to achieve its design goal, the designers equipped the language with structures that would make easy the correspondence between a software simulation and the physical system itself. The most important of these structures is the process. A process “is intended as an aid for decomposing a discrete event system into components, which are separately describable.”