Why C?

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Why C?

During the past three decades, C has become one of the most important and popular programming languages. It has grown because people try it and like it. In the past decade , many have moved from C to the more ambitious C++ language, but C is still an important language in its own right, as well a migration path to C++. As you learn C, you will recognize its many virtues (see Figure 1.1). Let's preview a few of them now.

Figure 1.1. The virtues of C.

Design Features

C is a modern language incorporating the control features found desirable by the theory and practice of computer science. Its design makes it natural for users to use top-down planning, structured programming, and modular design. The result is a more reliable, understandable program.

Efficiency

C is an efficient language. Its design takes advantage of the abilities of current computers. C programs tend to be compact and to run quickly. In fact, C exhibits some of the fine control usually associated with assembly language. If you choose, you can fine-tune your programs for maximum speed or most efficient use of memory.

Portability

C is a portable language. That means C programs written on one system can be run with little or no modification on other systems. If modifications are necessary, they can often be made by simply changing a few entries in a header file accompanying the main program. Of course, most languages are meant to be portable, but anyone who has converted an IBM PC BASIC program to Apple BASIC (and they are close cousins) or tried to run an IBM mainframe FORTRAN program on a UNIX system knows that porting is troublesome at best. C is a leader in portability. C compilers are available for about 40 systems, running from 8-bit microprocessors to Cray supercomputers. Note, however, that the portions of a program written specifically to access particular hardware devices ”such as a VGA monitor ”or special features of an operating system, such as Windows or System 7.1, typically are not portable.

You Can Take C Home

Because C is portable, you can take your UNIX C programs home to use on a personal computer. Several C compilers are available now to enable you to do that, or you can take your home-grown programs to a UNIX system.

Power and Flexibility

C is powerful and flexible (two favorite words in computer literature). For example, most of the powerful, flexible UNIX operating system is written in C. Many compilers and interpreters for other languages ”such as FORTRAN, APL, Pascal, LISP, Logo, and BASIC ”have been written in C. Therefore, when you use FORTRAN on a UNIX machine, ultimately a C program has done the work of producing the final executable program. C programs have been used for solving physics and engineering problems and even for animating special effects for movies such as Return of the Jedi.

Programmer Oriented

C is oriented toward the needs of programmers. It gives you access to hardware, and it enables you to manipulate individual bits in memory. It has a rich selection of operators that allow you to express yourself succinctly. C is less strict than, say, Pascal, in limiting what you can do. This flexibility is both an advantage and a danger. The advantage is that many tasks , such as converting forms of data, are much simpler in C. The danger is that with C, you can make mistakes that are impossible in some languages. C gives you more freedom, but it also puts more responsibility on you.

Also, most C implementations have a large library of useful C functions. These functions deal with many needs commonly facing the programmer.

Shortcomings

C does have some faults. Often, as with people, faults and virtues are opposite sides of the same feature. For example, we've mentioned that C's freedom of expression also requires added responsibility. C's use of pointers, in particular, means you can make programming errors that are very difficult to trace. As one computer preliterate once commented, the price of liberty is eternal vigilance .

C's conciseness combined with its wealth of operators make it possible to prepare code that is extremely difficult to follow. You aren't compelled to write obscure code, but the opportunity is there. After all, what other language has a yearly Obfuscated Code contest?

There are more virtues and, undoubtedly, a few more faults. Rather than delve further into the matter, let's move on to a new topic.

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