If you have variable and it’s value would not change, you can use the const keyword.  There is no way to change their value later, which means they are unchangeable and read-only.

example you have simple PI value and it is a fix value. You dont want to change it later

package main
import ("fmt")

const PI = 3.14

func main() {
  fmt.Println(PI)
}

*** important ***
DO NOT FORGET assign constant name in uppercase letters (this make easy identification and differentiation from variables)

const CONSTNAME type = value

example 1 :
const A int = 1 // sytax

 

example 2:
const A1 // also can be declared withour type, depend on goven value Go assinng a type 

 

example 3:
const (     // also possible assign multiple constans
A int = 1
B3.14
C“Hi!”
)