In the early 1990s the Borland company was one of the flagship in software development. They have produced lots of compilers and the Turbo Pascal language was the famous one. Many books were published about the subject and every computer magazine had a dedicated Pascal tutorial available. The language was teached in universities and nobody could imagine to use anything else.
Surprisingly, Borland resigned after a while. Today, the company is no longer active, and Turbo Pascal and everything around it is dead. That means, nobody is using the language and the old books are only available in antiquarian bookshop. What happened? The main reason why Turbo pascal failed was because operating systems programmed in Pascal were not powerful enough. And using the pascal language without an OS on bare-metal hardware doesn’t make much sense. Instead, modern operating systems like Linux and Windows were programmed in C/C++. The reason is, that C/C++ was powered by advanced compilers (Watcom, Microsoft, GNU) and the language was able to handle pointers. This makes it a great choice for writing lowlevel hardware drivers and for programming system libraries for graphics output.
An additional problem of Turbo Pascal was, that it doesn’t supported object oriented programming. All these problems together resulted in a abandoned programming language. In the mid 1980s it was not clear for most people who important dedicated operating systems are. In that area, the programmers were focussed on languages like BASIC and Pascal and there were focussed on hardware like the Atari SI or the Commodore 64. They used programming languages to program bare metal for a hardware and nobody thought about a layer in between them. The importance of a dedicated OS came later with the increasing complexity of software package. Today, it is normal to use existing library. If today a database application should print out the report on the gui and use a TCP/IP connection nobody would program the routines from scratch. Instead all the programmers are interested in saving time and they are using existing libraries which are integrated in operating systems.
The computer language which is best for writing operating systems is the king. And that is C/C++. If Pascal was chosen for writing the Windows kernel or the Linux kernel, then probably Pascal would use also for higher applications.
Pascal vs. C++
Turbo Pascal was the dominant language in the early 1990s. It was recognized as a beginners language and as a professional way to become familiar with computers. In the early 1990s nobody thought about C++. In that period, C++ was recognized as slow, because a C++ compiler needs much more RAM than a Pascal compiler, and C++ was not available on 16bit microcomputers. Even on mid-range computers on that period (Atari ST, Amiga series), the dominant languages were Assembly, C and Pascal. Computers from the early 1990s were not shipped with a full blown operating system which took 100s of Megabyte instead the OS-kernel was a simple 3.5” floppy disk or it was stored on the ROM chip in hardware.
The success of C++ came later in the late 1990s with the upraising of the PC desktop as a standard computer in mainstream and with full blown operating systems like WIndows NT and Linux. A operating system which consumes 800 MB on the harddrive an more need at the first hand better hardware, but it provides more gui-libraries for the programmer. These libraries simplify the programming.
For the non-expert is sounds crazy to call C++ an easy to use programming language. Because the specification needs 1000 pages and it takes month until a program runs smoothly. But compared to the technology before C++, it is easy-going.