Go Data Types

 Go Data Types – Complete Guide with Examples

In Go (Golang), data types define what kind of data a variable can store. Go is a statically typed language, which means every variable has a specific type known at compile time.

Understanding Go data types is essential for writing correct, efficient, and bug-free programs.

 What Are Data Types in Go?

A data type specifies:

• The kind of value a variable can hold

• How much memory it uses

• What operations can be performed on it

Example:

 Categories of Data Types in Go

Go data types are mainly divided into:

•  Basic Data Type
•  Composite Data Type
•  Reference Data Type

 1. Basic Data Type

 Integer Types

Used to store whole numbers.

Example:

 Floating-Point Type

Used for decimal numbers.

Boolean Type

Stores true or false.

•  Only true or false allowed

 String Type

Stores text data.

•  Strings are immutable
• Use double quotes

 Rune Type

Represents a single Unicode character.

• rune is an alias for int32.

2. Composite Data Types

 Array

Fixed-size collection of elements.

•  Size is fixed
•  Cannot grow

 Slice

Dynamic version of arrays.

•  Flexible
•  Most commonly used

 Struct

Used to group different data types.

•  Custom data type
•  Very powerful

 3. Reference Data Types

 Pointer

Stores memory address of a variable.

•  Efficient
•  Used to modify values

 Map

Stores key-value pairs.

•  Fast lookup
•  Reference type

Function Type

Functions are also data types.

• Can be passed as arguments

 Special Data Types

interface{} (Empty Interface)

Can hold any type.

•  Flexible
•  Use carefully

 byte

Alias for uint8.

•  Used for binary data

Type Inference in Go

Go automatically detects data type.

•  Cleaner syntax

 Zero Values in Go

If a variable is declared without initialization, Go assigns a zero value.

Type Conversion (Not Automatic)

Go does not allow implicit type conversion.

 Invalid

Valid

 Common Mistakes

•  Assuming automatic type conversion
•  Using wrong data type
•  Confusing array and slice
•  Ignoring zero values
• Overusing interface{}

 Best Practices

•  Use correct data type
•  Prefer slices over arrays
• Avoid unnecessary type conversions
• Use structs for related data
• Keep types simple

 Interview Questions: Go Data Type

1. Is Go statically typed?
Yes.

2. Default float type in Go?
float64.

3. What is a rune?
Alias for int32.

4. Are strings mutable in Go?
No.

5. What is zero value?
Default value of a type.

 Summary

•  Go has strong, static typing
•  Data type define value behavior
• Basic, composite, and reference types
• Zero values avoid uninitialized bugs
• Correct data type improve performance

Mastering Go data type is the foundation of clean, efficient, and professional Go programming