Learn Modula - 10 Code Examples & CST Typing Practice Test

Modula is a procedural programming language and modular systems language designed by Niklaus Wirth. It emphasizes strong typing, modularity, and simplicity, supporting the development of reliable, maintainable software systems.

View all 10 Modula code examples →

Simple Modula-2 Program Simple Modula-3 Program Modula-2 Fibonacci Sequence Modula-3 Factorial Program Modula-2 Array Sum Modula-3 While Loop Example Modula-2 Conditional Example Modula-3 Simple Function Modula-2 Nested Loops Modula-3 Record Example

Learn MODULA with Real Code Examples

Updated Nov 25, 2025

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Code Sample Descriptions

Simple Modula-2 Program

# modula2/demo.m2
MODULE Counter;
IMPORT InOut;
BEGIN
    FOR i := 1 TO 5 DO
        InOut.WriteInt(i, 0);
        InOut.WriteLn;
    END;
END Counter.

A simple Modula-2 program printing numbers 1 to 5.

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Simple Modula-3 Program

# modula3/demo.m3
MODULE Counter;
IMPORT IO;
BEGIN
    FOR i := 1 TO 5 DO
        IO.Put(i);
        IO.PutChar('\n');
    END;
END Counter.

A simple Modula-3 program printing numbers 1 to 5.

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Modula-2 Fibonacci Sequence

# modula2/fib.m2
MODULE Fibonacci;
IMPORT InOut;
VAR a, b, tmp, i: INTEGER;
BEGIN
    a := 0; b := 1;
    FOR i := 1 TO 10 DO
        InOut.WriteInt(a, 0);
        InOut.WriteLn;
        tmp := a + b;
        a := b;
        b := tmp;
    END;
END Fibonacci.

Calculates and prints Fibonacci numbers up to 10.

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Modula-3 Factorial Program

# modula3/factorial.m3
MODULE Factorial;
IMPORT IO;
VAR n, fact, i: INTEGER;
BEGIN
    n := 5; fact := 1;
    FOR i := 1 TO n DO
        fact := fact * i;
    END;
    IO.Put(fact);
    IO.PutChar('\n');
END Factorial.

Calculates factorial of 5 and prints the result.

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Modula-2 Array Sum

# modula2/array_sum.m2
MODULE ArraySum;
IMPORT InOut;
VAR arr: ARRAY 1..5 OF INTEGER := (1,2,3,4,5);
    sum, i: INTEGER;
BEGIN
    sum := 0;
    FOR i := 1 TO 5 DO
        sum := sum + arr[i];
    END;
    InOut.WriteInt(sum,0);
    InOut.WriteLn;
END ArraySum.

Sums elements of an integer array.

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Modula-3 While Loop Example

# modula3/while_loop.m3
MODULE WhileDemo;
IMPORT IO;
VAR i: INTEGER;
begin
    i := 1;
    WHILE i <= 5 DO
        IO.Put(i);
        IO.PutChar('\n');
        i := i + 1;
    END;
END WhileDemo.

Prints numbers from 1 to 5 using a WHILE loop.

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Modula-2 Conditional Example

# modula2/if_example.m2
MODULE EvenOdd;
IMPORT InOut;
VAR n: INTEGER;
BEGIN
    n := 7;
    IF n MOD 2 = 0 THEN
        InOut.WriteString("Even");
    ELSE
        InOut.WriteString("Odd");
    END;
    InOut.WriteLn;
END EvenOdd.

Checks if a number is even or odd.

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Modula-3 Simple Function

# modula3/double.m3
MODULE DoubleFunc;
IMPORT IO;
PROCEDURE Double(x: INTEGER): INTEGER;
BEGIN
    RETURN 2*x;
END Double;

BEGIN
    IO.Put(Double(5));
    IO.PutChar('\n');
END DoubleFunc.

Defines a function to double a number and prints the result.

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Modula-2 Nested Loops

# modula2/mult_table.m2
MODULE Table;
IMPORT InOut;
VAR i,j: INTEGER;
BEGIN
    FOR i := 1 TO 5 DO
        FOR j := 1 TO 5 DO
        InOut.WriteInt(i*j,0);
        InOut.WriteString(" ");
        END;
        InOut.WriteLn;
    END;
END Table.

Prints a 5x5 multiplication table.

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Modula-3 Record Example

# modula3/record.m3
MODULE PointDemo;
IMPORT IO;
TYPE Point = RECORD x,y: INTEGER END;
VAR p: Point;
BEGIN
    p.x := 10; p.y := 20;
    IO.Put(p.x);
    IO.PutChar(',');
    IO.Put(p.y);
    IO.PutChar('\n');
END PointDemo.

Defines a record type for a point and prints its coordinates.

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Frequently Asked Questions about Modula

What is Modula?

What are the primary use cases for Modula?

Teaching structured and modular programming. Systems and embedded programming. Research in programming languages and compilers. Developing reliable software with modular architecture. Prototyping software with clear separation of concerns

What are the strengths of Modula?

Encourages clean and maintainable code. Modules enable code reuse and encapsulation. Strong typing reduces runtime errors. Suitable for teaching structured programming concepts. Clear separation of interface and implementation

What are the limitations of Modula?

Not widely adopted in modern industry. Limited libraries and tooling compared to modern languages. Mostly of historical and educational interest. Verbose syntax compared to contemporary languages. Concurrency and modern paradigms not inherently supported

How can I practice Modula typing speed?

CodeSpeedTest offers 10+ real Modula code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.

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Code Sample Descriptions

Simple Modula-2 Program

# modula2/demo.m2
MODULE Counter;
IMPORT InOut;
BEGIN
    FOR i := 1 TO 5 DO
        InOut.WriteInt(i, 0);
        InOut.WriteLn;
    END;
END Counter.

A simple Modula-2 program printing numbers 1 to 5.

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Simple Modula-3 Program

# modula3/demo.m3
MODULE Counter;
IMPORT IO;
BEGIN
    FOR i := 1 TO 5 DO
        IO.Put(i);
        IO.PutChar('\n');
    END;
END Counter.

A simple Modula-3 program printing numbers 1 to 5.

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Modula-2 Fibonacci Sequence

# modula2/fib.m2
MODULE Fibonacci;
IMPORT InOut;
VAR a, b, tmp, i: INTEGER;
BEGIN
    a := 0; b := 1;
    FOR i := 1 TO 10 DO
        InOut.WriteInt(a, 0);
        InOut.WriteLn;
        tmp := a + b;
        a := b;
        b := tmp;
    END;
END Fibonacci.

Calculates and prints Fibonacci numbers up to 10.

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Modula-3 Factorial Program

# modula3/factorial.m3
MODULE Factorial;
IMPORT IO;
VAR n, fact, i: INTEGER;
BEGIN
    n := 5; fact := 1;
    FOR i := 1 TO n DO
        fact := fact * i;
    END;
    IO.Put(fact);
    IO.PutChar('\n');
END Factorial.

Calculates factorial of 5 and prints the result.

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Modula-2 Array Sum

# modula2/array_sum.m2
MODULE ArraySum;
IMPORT InOut;
VAR arr: ARRAY 1..5 OF INTEGER := (1,2,3,4,5);
    sum, i: INTEGER;
BEGIN
    sum := 0;
    FOR i := 1 TO 5 DO
        sum := sum + arr[i];
    END;
    InOut.WriteInt(sum,0);
    InOut.WriteLn;
END ArraySum.

Sums elements of an integer array.

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Modula-3 While Loop Example

# modula3/while_loop.m3
MODULE WhileDemo;
IMPORT IO;
VAR i: INTEGER;
begin
    i := 1;
    WHILE i <= 5 DO
        IO.Put(i);
        IO.PutChar('\n');
        i := i + 1;
    END;
END WhileDemo.

Prints numbers from 1 to 5 using a WHILE loop.

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Modula-2 Conditional Example

# modula2/if_example.m2
MODULE EvenOdd;
IMPORT InOut;
VAR n: INTEGER;
BEGIN
    n := 7;
    IF n MOD 2 = 0 THEN
        InOut.WriteString("Even");
    ELSE
        InOut.WriteString("Odd");
    END;
    InOut.WriteLn;
END EvenOdd.

Checks if a number is even or odd.

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Modula-3 Simple Function

# modula3/double.m3
MODULE DoubleFunc;
IMPORT IO;
PROCEDURE Double(x: INTEGER): INTEGER;
BEGIN
    RETURN 2*x;
END Double;

BEGIN
    IO.Put(Double(5));
    IO.PutChar('\n');
END DoubleFunc.

Defines a function to double a number and prints the result.

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Modula-2 Nested Loops

# modula2/mult_table.m2
MODULE Table;
IMPORT InOut;
VAR i,j: INTEGER;
BEGIN
    FOR i := 1 TO 5 DO
        FOR j := 1 TO 5 DO
        InOut.WriteInt(i*j,0);
        InOut.WriteString(" ");
        END;
        InOut.WriteLn;
    END;
END Table.

Prints a 5x5 multiplication table.

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Modula-3 Record Example

# modula3/record.m3
MODULE PointDemo;
IMPORT IO;
TYPE Point = RECORD x,y: INTEGER END;
VAR p: Point;
BEGIN
    p.x := 10; p.y := 20;
    IO.Put(p.x);
    IO.PutChar(',');
    IO.Put(p.y);
    IO.PutChar('\n');
END PointDemo.

Defines a record type for a point and prints its coordinates.

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Frequently Asked Questions about Modula

What is Modula?

What are the primary use cases for Modula?

What are the strengths of Modula?

What are the limitations of Modula?

How can I practice Modula typing speed?

CodeSpeedTest offers 10+ real Modula code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.