**Procedures** in Pascal are declared using the `procedure` keyword, as shown in the code snippet below:
```C
procedure _procName_ (_parameter(s)_: _parameterType_;, _parameter(s)_: _parameterType_;, ...); 
_localDeclarations_
begin
   //procedure body
end;
```
* **`_procName_`**: The name of the procedure.
* **`_argument(s)_`**: The arguments that are passed to the procedure.
* **`_parameterType_`**: The data type of the arguments passed.
* ﻿﻿**`_localDeclarations_`**: Declarations such as variables, constants, functions﻿, etc.﻿ that are referred ﻿to in the `procedure body`.




# Examples
## Example 1
Consider a simple example of a procedure that calculates the sum of two numbers:

program Example1;
var
   a, b, calSum : integer;
   
procedure sum(a, b: integer; var calSum: integer);
var
   tempSum: integer;//local Declaration

begin
   calSum := a + b;
end;

begin
   a := 5;
   b := 10;
   sum(a, b, calSum);
   writeln(a, ' + ', b, ' = ', calSum);
end.

pascal

## Explanation
* *Lines 5-11*: The `sum()` procedure is declared that takes three parameters, `a`,  `b`, and `calSum`. The `sum()` procedure calculates the mathematical sum of `a` and `b` in *line 10* and stores the sum in a *variable parameter*, `calSum`. As `calSum` is a *variable parameter*, changing its value in the procedure will be propagated back to the main block. So, we can store the sum in `calSum` and access the sum in main.
* *Line 16*: The `sum()` procedure is called in *line 16* and is passed with `a`, `b`, and `calSum` as parameters. 

## Example 2
Consider an example of a procedure with no parameters:


program Example2;
   
procedure noParam();
begin
   writeln('This is a procedure with no parameters');
end;

begin
   noParam();
end.

pascal.tar.gz

How to declare a procedure in Pascal

Procedures in Pascal use the keyword 'procedure', include parameters, body, and local declarations, and can modify passed variables.