The evolution of electronic computers began I the 1940's.early efforts in the field of computing where focused on designing the hardware ,as that was the challenge , and hardware was where most technical difficulties existed. In the early computing systems ,there was essentially on operating system, and the ptograms were fed with paper taps or by switches .With the evolutiopn of second generation .
Machines in the 1950's yearly concepts of operating systems evolved and signal user operating syastems came into existence. High level languages ,practically FORTRAN & COBOL ,along with there compilers were developed .There was a gradual trend towards isolating the user from the machine internals ,so the getting blogged down with the machine details .
With the coming of the multiprogramming operating systems in the early 1960's the usability and efficiecy of the computing machines took a big leap .Prices of hardware also decreased ,and awerness of computing machines took a big leap. Prices of hardware also decreased ,and awereness of computers increased substantially since their early days .With the availibility of cheaper and more powerful machines ,higher level languages ,and more user friendly- operating systems ,the applications of computer grew rapidly .
In addition ,the nature of software engineering evolved from simple programming exercise to developimg many people .
The techniques for writing simple programs could not be scaled up t developing software systems , and the computing world found itself in the midst of a " software crisis " .two conferences ,sponsered by NATO Science Committee ,were held in Europe in 1960's to discusthe growing software crisis and the need to focuson the software development.