The origin and development history of C language

The origin and development history of C language

As a widely used computer programming language, C language has the characteristics of simplicity, efficiency, portability, etc. It is an important part of the computer field. One of the most indispensable languages. This article will describe the origin, development history of C language and some specific code examples.

1. The Origin of C Language
The origin of C language can be traced back to 1969 to 1973, and was developed by Dennis Ritchie of Bell Labs in the United States. Originally, the C language was designed for writing UNIX operating systems. In order to make it easier to port UNIX systems, Dennis Ritchie and his colleague Brian Kernighan developed the C language on the PDP-7 and PDP-11 hardware. C language borrowed some features of B language, and after continuous improvement and development, it finally formed C language in the modern sense.

2. The development history of C language

1. In 1972, the first UNIX operating system written in C language was released. The simplicity and efficiency of C language make the development of UNIX systems more convenient.
2. In 1978, Kernighan and Ritchie co-authored "The C Programming Language". This book systematically introduced the grammar and applications of C language and became a standard textbook on C language.
3. In 1983, the American National Standards Institute (ANSI) formulated the C language standard, namely ANSI C.
4. In 1989, the International Organization for Standardization (ISO) agreed to use the ANSI C standard as an international standard and determined the ISO C standard for the C language.
5. In 1999, the ISO C99 standard was released, adding a series of new features and further improving the functions of the C language.
6. In 2011, the ISO C11 standard was released, which continued to expand the functions and features of the C language, making the C language more powerful and flexible.

3. C language code examples
The following are some simple code examples to show the basic syntax and features of C language.

1. Hello World

   #include <stdio.h>
   
   int main() {
    printf("Hello World
   ");
    return 0;
   }

2. Variables and operators

   #include <stdio.h>
   
   int main() {
    int a = 5;
    int b = 3;
    int sum = a b;
    
    printf("The sum of a and b is: %d
   ", sum);
    
    return 0;
   }

3. Conditional statement

   #include <stdio.h>
   
   int main() {
    int num = 10;
    
    if (num > 5) {
        printf("The number is greater than 5
   ");
    } else {
        printf("The number is less than or equal to 5
   ");
    }
    
    return 0;
   }

Through the above code examples, we can see the basic syntax structure of C language, including header file references, variable definitions, function definitions, conditional statements, etc. The simplicity and efficiency of C language make it one of the favorite programming languages ​​​​of many programmers.

Summary: As a programming language with a long history and powerful functions, C language has played an important role since its inception. Its concise grammatical structure and efficient execution efficiency have made C language widely used in systems programming, embedded development and other fields, and also influenced the design and development of many subsequent programming languages. With the continuous advancement of technology, the C language is also constantly evolving. It is still of great significance to keep pace with the times.

The above is the detailed content of The origin and development history of C language. For more information, please follow other related articles on the PHP Chinese website!