Dharani Tech Edu Hub

Type Conversion & Casting in C

---

Introduction

In C programming, sometimes we need to convert one data type into another. This process is called Type Conversion.

👉 It is very useful when performing operations between different data types.

There are two types:

• Automatic Type Conversion
• Type Casting (Manual Conversion)

---

What is Type Conversion?

Type conversion means converting a value from one data type to another.

👉 Example:

int a = 10;
float b = a;   // int → float

---

1. Automatic Type Conversion (Implicit Conversion)

This is done automatically by the compiler.

👉 Smaller data type → Bigger data type

---

Example

#include <stdio.h>

int main() {
    int a = 10;
    float b;

    b = a;  // automatic conversion

    printf("Value of b = %f", b);

    return 0;
}

---

Output

Value of b = 10.000000

---

Key Points

• ✔ Done automatically
• ✔ No data loss
• ✔ Safe conversion

---

2. Type Casting (Explicit Conversion)

Type casting is done manually by the programmer.

👉 Syntax:

(data_type) expression

---

Example

#include <stdio.h>

int main() {
    float a = 5.8;

    int b = (int)a;  // manual conversion

    printf("Value of b = %d", b);

    return 0;
}

---

Output

Value of b = 5

---

Explanation

• float 5.8 → converted to int
• Decimal part is removed
  👉 Result = 5

---

Difference Between Type Conversion & Type Casting

Feature	Type Conversion	Type Casting
Control	Automatic	Manual
Done By	Compiler	Programmer
Syntax	No syntax needed	(data_type)
Data Loss	No	Possible

Common Mistakes

• ❌ Ignoring data loss during casting
• ❌ Using wrong data type
• ❌ Confusing implicit and explicit conversion

---

Pro Tips

• ✔ Use casting carefully
• ✔ Prefer automatic conversion when safe
• ✔ Always check precision loss
• ✔ Practice mixed data type operations

---

Conclusion

Type conversion and casting are important concepts in C programming. They help in handling different data types efficiently and ensure smooth program execution.

👉 This article is part of Dharani Tech Edu Hub — where learning programming is made simple and practical.