Basics of Programming : Variables

Variables

Before going into definition of variable, let us consider any mathematical equation which we have studied in our schools.

For example consider, 2x + 5y = 35

We do not have to know the use of this equation, but we just know that we can substitute some values for x and y which can satisfy the equation. For example (x,y) can take values (10, 3) or (5, 4). So we can say that x and y can hold some values or x and y can are placeholders for some data.

In the same way we need something for holding data in computers. Those are called as variables.

In other words we can also say that, variables are the name given for memory location. Since data are stored in some memory location, variables are the labels for those memory locations.

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