As the name suggests, data-type specifies the type of the data present in the variable. Variables must be declared with a data-type.

1. Numeric Data types

Integer Data types

Data type	Description	Size	Range
uint8	8-bit unsigned integer	1 byte	0 to 255
int8	8-bit signed integer	1 byte	-128 to 127
int16	16-bit signed integer	2 bytes	-32768 to 32767
unit16	16-bit unsigned integer	2 bytes	0 to 65,535
int32	32-bit signed integer	4 bytes	-2,147,483,648 to 2,147,483,647
uint32	32-bit unsigned integer	4 bytes	0 to 4,294,967,295
int64	64-bit signed integer	8 bytes	-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
uint64	64-bit unsigned integer	8 bytes	0 to 18,446,744,073,709,551,615

Float Data types

Data type	Description
float32	32-bit signed floating point number
float64	64-bit signed floating point number
complex32	Number has float32 real and imaginary parts
complex64	Number has float32 real and imaginary parts

2. Boolean Data types

Data type	Description	Size	Range
bool	Stores either true or false	1 byte	True or false

3. String Data types

Data type	Description
string	sequence of characters

Example

package main

import (
	"fmt"
	"math/cmplx"
)

var (
	integer uint32 =  1<<32 - 1
	flt float64 = 3.14
    complexNum complex128 = cmplx.Sqrt(8 - 6i)
    str string = "Hello World"
    boolean bool = true
)

func main() {
	fmt.Printf("Value: %v is of Type: %T\n", integer, integer)
	fmt.Printf("Value: %v is of Type: %T\n", flt, flt)
	fmt.Printf("Value: %v is of Type: %T\n", complexNum, complexNum)
	fmt.Printf("Value: %v is of Type: %T\n", str, str)
	fmt.Printf("Value: %v is of Type: %T\n", boolean, boolean)
}

Check result here