Originally, the C programming language was developed in England, under the name of BCPL. Then, in 1972, Americans Brian Kernigham and Dennis Ritchie transformed BCPL to a programming language called B. Finally, in 1974, the programming language was modified and improved, finally to be renamed "C."
Not exactly a high-level language like BASIC, PASCAL, and C++, C is somewhere between a low-level programming language and a high-level programming language. Low-level languages were hard and arduous to use because everything had to be written in the 1s and 0s that a computer can directly understand. While high-level languages use more human language-like terms, it is less efficient. C was developed to try to combine the efficiency of the low-level languages and yet keep the good structure of the high-level languages.
Ever since it was developed, C has become increasingly popular. As you know, programming languages can be used to write software and applications. The C language was first used to write the UNIX operating system. This really helped to popularize it, especially among computer programmers.
Components:
All C programs essentially have two basic components:
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Statements are the parts of the C program that perform the operations and tasks. This is where the instructions are contained. You end a statement with a semicolon.
2. Functions
For the C program to recognize what the functions are, you need to give each function a name. Basically, you can give a function any name you want, except you can only use letters, numerical digits, and the underscore. Also, C is case-sensitive. This means that it recognizes upper and lower cases as different characters. Thus, a function with the name "Function" would be different from a function with the name "function."
Below are three examples of functions that a C program can contain:
When you first open a C program, it will automatically carry out the instructions found in the statements contained in the main() function. The statements for the function are written between the parentheses.
The printf() function is a basic output function. It outputs characters contained in quotation marks between the parentheses.
The scanf() function is often used to input numbers into the program.
3. Variables
First, there is the character type. It is usually 8 bits long and can hold a single letter, number, or other character.
Second, there's integer. In math, you might have learned about integers. These are the numbers without a fractional part. The integer variables hold, well, integers.
Third, there are float type variables. These can hold numbers that do have a fractional part.
Fourth, there are the double variables. Like the float variables, the double variables can also hold numbers with a fractional part. However, these variables can hold more digits than the float type variables.
Finally, there are void variables. These are for special-purpose data types.
To perform certain arithmetic operations, the C programming language must
define operations like addition, subtraction, multiplication, and division.
In C, these symbols are almost exactly like the ones we use in algebra:
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| / | Division |
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