Page 99 - Computer Genius Class 06
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Create/Declare a Variable

                 Syntax is a rule which must be followed while performing a task.
                 In most of the programming languages, you can declare a variable by using the following syntax:

                 Datatype VariableName=Value;

                 Example: Declaring a variable.
                 int x=20
                 int y=30
                 int x, int y will create two variables ‘x’ and ‘y’ and it reserve two memory locations with names ‘x’ and
                 ‘y’. Variables are created by using the ‘int’ keyword. ‘int’ specify the data type which means that the
                 declared variable will store integer values ‘20’ and ‘30’ in these two variables.
                 Once the variable is created, you need to assign it a value before using it. This process of assigning
                 a value to a variable is called initialization.

                    aria le  hich is declared  ut is not initiali ed e er has an undefined  alue   ut you can assign it
                 a value in later steps by using assignment operators.
                 Consider example 1, in which two variable ‘x’ and ‘y’ are declared. Variable ‘x’ stores a value ‘20’ and
                 variable ‘y’ stores a value ‘30’.
                 Now, when the program is executed, the memory location named as ‘x’ will hold a value ‘20’ and
                 memory location named as ‘y’ will hold a value ‘30’.














                 As you already know that a variable cannot be used unless a value is assigned to it. The value of a
                  aria le can  e initiali ed to   ull    hich is also a  alue.  aria le  hich is defined  ith the   ull
                 value is a variable which is not initialized and also it does not hold any value, not even ‘Null’. In
                 some programming languages like Python, there is no command to declare the variables. A variable
                 is created at the moment   hen you first assign a  alue to it.

                 Example: Declaring a variable in Python.
                 x=7
                 y=“Orange Education”

                 Data Types in Programming

                  ata type identifies the type o  data  hich the declared  aria le can hold.  t helps the computer to
                 understand what operations need to be performed on the declared variables.
                 To declare the variable, you need to define:

                   name of the variable

                   its type

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