Java Programming History

[shchamon]

Initially, computers were hard-wired and then later programmed using binary code that represented control sequences fed to the computer central processing unit (CPU). This was difficult and error-prone. The transfer from hard wiring to machine code represents the implementation of the Von Humane machine. A hardwired system reflects a machine with a transfer function for the data between input and output. The function is created by the wiring and components between the two. A later machine incorporates the stored program concept exemplified by a Von Neumann machine where data and program are both stored in the same machine. In the Von Neumann machine each program represents a different hardwired machine. The program defining the transfer functions for data.

Programs written in binary are said to be written in machine code. Which is a very low-level programming paradigm? To make programming easier, assembly languages were developed. These replaced machine code functions with mnemonics and memory addresses with symbolic labels. Assembly language programming is considered a low-level paradigm although it is a 'second generation' paradigm. Even assembly languages of the 1960s actually supported library COPY and quite sophisticated conditional macro generation and per-processing capabilities. They also supported modular programming features such as CALL (subroutines), external variables and common sections (globe’s), enabling significant code re-use and isolation from hardware specifics via use of logical operators as READ/WRITE/GET/PUT. Assembly was, and still is, used for time critical systems and frequently in embedded systems.